kir10 - World Radio History
60
(1101 kir10 TECHNICAL ARTICLES Stereo Discs Cartridges Needles Stereocasting FM/AM Multiplex Speakers Changers Turntables Tape Recorders Master Control Converting to Stereo Glossary PRODUCT CATALOG Photographs of Equipment Prices Technical Specifications DIRECTORY OF MANUFACTURERS Names Addresses Products -Calk 1,"11111111 II Published by ELECTRONIC TECHNICIAN Magazine
Transcript of kir10 - World Radio History
(1101
kir10 TECHNICAL ARTICLES
Stereo Discs Cartridges Needles
Stereocasting FM/AM Multiplex
Speakers Changers Turntables
Tape Recorders Master Control
Converting to Stereo Glossary
PRODUCT CATALOG
Photographs of Equipment Prices
Technical Specifications
DIRECTORY OF MANUFACTURERS
Names Addresses Products
-Calk
1,"11111111 IIPublished by ELECTRONIC TECHNICIAN Magazine
The latest high fidelity developments from Rek-O-Kut Co., Inc., 38-19 108th St., Corona 68, N. Y.
TURNTABLE NEED IN STEREO MET BY NEW RONDINES!Expanded Rek-O-Kut Line Covers All Levels of Consumer
Demand - New Low Prices Start at $39.95.
Single -Speed in Kit Form-$39.95
SPECIFICATIONS Model K-33
Assembly Time: Approximately 30minutes with simple tools. Mount-ing template suppliedNoise Level: 47 db.Motor: Induction-4-pole-built toRek-O-Kut specifications.Speed: 331/3 rpm.Belt: Special endless woven fabricwith thickness held to ± .001.Adjustment for belt tension.Built -In Strobe Disc: For checkingspeed.Minimum Dimensions For CabinetInstallation With Rek-O-Kut S-120Arm: 173,4 x 163/8.Turntable: Tapered for easy dischandling. Solid cast aluminumlathe -turned.
3 -speed Hysteresis
Synchronous Motor-$99.95
SPECIFICATIONSModel B-12GHNoise Level: 53 db.Motor: New design, self-lubricating, Hysteresis Synchronous.Speeds: 331/3, 45 and 78 rpm.Speed Selection: Single selector knob. Idler is disengaged in"off" position.Built -In Strobe Disc: For checking speeds.45 RPM Hub: Built-in retractable.Pilot Light: Jewelled neon light acts as "on/off" indicator.Chassis Deck: Cross -ribbed cast aluminum. Designed forflush -mounting in rectangular cut-out.Minimum Dimensions For Cabinet Installation With Rek-O-Kut S-120 Arm: Left to Right 173/4; Front to Back 16"; Heightabove Deck 3"; Height below Deck 61/2".Turntable: Solid cast aluminum-lathe-turned. Tapered foreasy disc handling.
Single -Speed Hysteresis
Synchronous Motor-$69.95
SPECIFICATIONS Model N -33H
Noise Level: 53 db.Motor: New design, self-lubricat-ing, Hysteresis Synchronous withspecial breaking for reduction ofcoasting.Speed: 331/3 rpm.Belt: Special endless woven fabricwith thickness held to -± .001.Adjustment for belt tension.Built -In Strobe Disc: For checkingspeed.Chassis Deck: 157/8x 15 AluminumMinimum Dimensions For CabinetInstallation With Rek-O-Kut S-120Arm: 173/4 x 163/8.Turntable: Solid Cast Aluminumlathe -turned. Tapered for easy dischandling.
All -New Rondines Offer Matchless Performance- Fashion -Keyed Styling!With the new advanced Rondines,
Rek-O-Kut has again set performancestandards far beyond any consistentattainment by other brands! In addi-tion to great new operational perform-ance and convenience, Rek-O-Kut hasadded fashion -keyed styling with strik-ing designs created by George Nelson,noted industrial designer. The lathe -turned cast -aluminum tables are nowtapered for easy disc handling and thecompact, modern over-all turntabledecor is highlighted by the attractivefinish in black and aluminum.
HUAI IDLLITY
The K-33 belt -drive Rondine inkit form answers the tremendous de-mand by the budget -conscious "teen-age," and college groups, as well as the"do-it-yourself" fans. Even with a Rek-O-Kut or Audax Tonearm Kit, the K-33 matches or betters the price of"High Fidelity" changers! Simple as-sembly with ordinary tools can be ac-complished in less than thirty minutes!
Owners and buyers of more elabo-rate stereo component systems will wel-come the advent of the single speedand 3 -speed Rondines with hysteresis
synchronous motors at unprecedentedlow prices. This broad selection is fur-ther widened by the continued avail-ability of the famous Rondine Deluxe(B -12H) with custom hysteresismotor and the ever -popular 2 -speedRondine Juniors (L-34 and L-37).
Ask About the New Rek-O-Kut StereoTonearms - also Stereo ConversionKits for converting A-120 and A-160Arms to Stereo.
WRITE FOR LATEST CATALOG
ENGINEERED FOR THE STUDIO...DESIGNED FOR, THE HOMEExport. Morhan Exporting Corp., 458 Broadway, N. Y. 13 Canada: Atlas Radio Corp. 50 Wingold Ave., Toronto 10, Ont.
42Circle 42-01 on inquiry form page 73
ELECTRONIC TECHNICIAN Stereo, 1959
STERKa '195CONTENTS
Entire STEREO 195S Contents on Pages 41-100
FEATURES and ARTICLESThe Meaning of StereoStereo Discs-Two Channels In One GrooveMaster Control for StereoConverting to StereoThe Stereo CartridgeNeedles for StereoMultiplex StereocastingStereo Tape and Tape RecordersSpeaker Arrangements for StereoChangers and Turntables for StereoReaders Inquiry CardStereo Glossary
PRODUCT CATALOG
474850525456606466717398
Amplifiers & Preamps 75 Microphones 81
Arms 77 Speakers & Enclosures .... ....... 81
Cartridges 78 Tape P.ecorders 84
Changers 79 Tuners 85Control Units & Adapters 8D Turnta3les 86
Conversion Kits 80
BUYERS DIRECTORYAmplifiers, Preamplifiers & Controls .. 88 Speakers & Cabinets 89Cartridges, Stereo Phono 88 Tape 90Changers, Turntables & Arms 88 Tape Recorders, Playbacks &Conversion Kits 88 Accessories 90Microphones & Accessories 89 Tuners 90Needles, 0.5 or 0.7 Mil 89 Alpha3etical List of Manufocturers 91
Phonograph Systems 89 Indust -y Associations 93Records, Stereo 89
ALBERT J. FORMAN ROBERT CORNELLEditor Technical Editor
NORMAN CROWHURST B. V. SPINETTA CHARLES DREYERStereo Consultant D rectory Editor Art Director
STEREO 1959 is published by ELECTRONIC TECHNICIANMagazine, the leading technical journal of the audio -electronic maintenance field. Printed in U.S.A. 50i% per copy.
Copyright 1958 by Electronic Technician, Inc.,480 Lexington Avenue, New York 17, N.Y.
HOWARD A. REED, President
Carat 14.01 sit inquiry f QOM 113
LT
*T
LTE
Rw
ithE
BSt
ereo
's S
tand
ard
DC
T
cost
ing
betw
een
'60-
$90
'140
-$2
00
Incl
udes
an
8" c
oaxi
al s
peak
er s
uch
as:
E -
V C
OR
ON
ET
*(w
ith S
P81
3), N
et $
65E
-V B
AR
ON
ET
*(w
ith S
P8B
), N
et $
74.5
0
SP
88. W
ide
rang
e, e
cono
mic
al, s
uper
-ef
fi-ci
ent c
oaxi
al s
peok
er. S
mal
l hig
h -f
requ
ency
prop
agat
or in
sure
s fin
e di
sper
sion
.
Incl
udes
a tw
o-w
ay s
epar
ate
syst
em s
uch
as:
E -
V C
OR
ON
ET
IA
,N
et $
102
E -
V B
AR
ON
ET
III
,N
et $
111.
50E
-V
RE
GA
L I
A,
Net
$10
3
or in
clud
es a
12"
coa
xial
spe
aker
suc
h as
:E
-V
MA
RQ
UIS
' with
SP
128)
, Net
$98
E -
V A
RIS
TO
CR
AT
* (w
ith S
P12
8),
Net
$10
73F
188.
Add
ed e
ffiLl
e,n.
, «Ill
. luw
e,no
nce.
Ext
ends
fund
amen
tal l
ow r
ange
Fxr
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nt d
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n te
r w
ides
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reo
effe
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peak
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uch
as.
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TR
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, Nut
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RIS
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AT
(w
ith 1
2TR
XB
I,N
et $
138
12T
RX
8: H
as a
ll th
e fe
atur
es o
f the
SP
I28-
plus
a s
epar
ate
high
-fr
eque
ncy
driv
er w
ithel
ectr
ical
cro
ssov
er fo
r st
ill lo
wer
dis
tort
ion.
Giv
es w
ides
t spr
ead
of v
ital s
tere
o ra
nge
toba
leve
twig
c sl
e,eg
Ilsl
etili
ly L
ima.
"1,
CK
CA
L I
II
RE
GA
LS
uper
-co
mpa
ct, s
pe-
dully
des
igne
d sy
stem
with
luilu
ied
kk.im
putia
tilk
lu g
ive
enlic
sim
edra
nge
and
purit
y of
tone
with
leas
t los
s of
effic
ienc
y. D
oes
not r
equi
re h
igh
pow
ered
ampl
ifier
. Net
$14
7.50
Imita
tor,
a 1
5" th
ree
way
spe
aker
tueh
et,
E -
V E
MP
IRE
' (w
ith 1
5TR
XB
1, N
et $
178
Em
pirv
ie.1
5TR
X43
. Sim
ilar
to12
TR
XB
, but
will
,ad
ded
bass
effi
cien
cy fr
om J
orge
con
e, a
ndde
liver
ing
low
er b
ass
resp
onse
.
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V s
.yst
ellly
W11
101
Gill
UU
With
I$
-V B
LO
M-
ing
Blo
cks
whe
neve
r yo
ur b
udge
t per
mits
.
NO
TE
: All
E -
V e
nclo
sure
s al
so a
vaila
ble
in li
med
oak
or w
alnu
t fin
ishe
s.
You
nee
d th
eto
tally
com
patib
leE
-V
ST
ER
EO
CA
RT
RID
GE
* th
e fir
st s
tere
o ca
rtrid
ge
X:
the
only
fiel
d te
sted
ste
reo
cart
ridge
Tho
usan
ds a
lread
y In
use
pro
ve it
* P
lays
ALL
RE
CO
RD
S B
ET
TE
RU
nexc
elle
d fo
r st
ereo
, sup
erio
r ev
en to
your
pre
sent
car
trid
ge fo
r m
onau
ral
* H
ighe
st v
ertic
al a
nd h
oriz
onto
lco
mpl
ianc
eF
or s
uper
ior
trac
king
,lo
nges
t rec
ord
wea
r
* B
est c
hann
el s
epar
atio
nov
er 2
0 db
bet
wee
n ch
anne
ls
.4.
Flu
tter:
res
pons
eF
lat b
eyon
d au
dibi
lity
to R
IAA
cur
ve
'I'I l
um s
. ,J
mag
netic
car
trid
ge*
Tw
o ce
ram
ic e
lem
ents
del
iver
pre
cise
RIA
A c
urve
with
no
hum
!
* E
xclu
sive
E -
V B
uilt-
in V
ertic
al R
umbl
eS
uppr
esso
r al
low
s re
cord
cha
nger
use
for
ster
eo
* .7
-w
it re
plac
eabl
e (d
iam
ond
orsa
pphi
re)
styl
us is
the
idea
l siz
e ...
give
s yo
u be
tter
repr
oduc
tion,
long
er r
ecor
d w
ear
The
n ch
oose
a s
econ
d am
plifi
er a
nd p
re-
umpl
Itler
. 111
111s
Is y
uur
1410
Idyl
l fid
elity
syst
em,
star
t with
any
ste
reop
honi
c du
alot
sitli
fieie
tteot
teili
flet
Plo
y st
otto
ttottl
y tie
.til
you
add
a s
econ
d sp
eake
r fo
r st
ereo
.
nnnnnn
The
F -
V T
otal
ly C
omae
ihle
Ste
reo
Car
trid
ge is
the
indu
stry
's s
tand
ard.
Cho
ose
the
mod
el to
fit y
our
need
s:M
OD
EL
21D
-Ste
reo
with
.7 -
mil
Dia
mon
dS
tylu
s, N
et $
19.5
0
MO
DE
L 2d
DC
T..
Due
l atla
s T
urno
,cr
from
.7 -
mil
Dia
mon
d S
tere
o to
3 -
mil
Sap
phire
Mon
nurn
i Net
577
50
or th
e E
-V
Vel
ocity
Ste
reo
Car
trid
geM
OD
EL
2IM
D-S
tere
o w
ith .7
-m
il D
iam
ond
Sty
lus,
Net
$19
.50
MO
DE
L 2
6mD
ST-D
ualS
tylu
s T
urno
ver
from
7.m
ilif.
ron
inS
apph
ireM
onau
ral,
Net
$22
.50
I.
Add
-on
E -
V B
AR
ON
ET
*...
smal
lest
fold
ed -
horn
cor
ner
encl
osur
e fo
rbe
st m
usic
alba
lanc
e an
d re
spon
se r
ange
: phe
nom
onot
bas
s ra
nge,
exte
nded
two
full
octa
ves.
Mat
ches
the
Cor
onet
and
oth
er
com
para
ble
spea
ker
syst
ems.
With
SIM
, Net
$74
.50,
or
BA
RO
NE
T II
I with
SP
88 a
nd 7
35B
VH
F d
river
, Net
$11
1.50
Add
-on
E -
V A
RIS
TO
CR
AT
t...
popu
lar
fold
ed -
horn
cor
ner
encl
osur
e ...
com
pact
,ec
onom
ical
.de
liver
sm
ost
exte
nded
bas
s ra
nge
for
itssi
ze. W
ithS
P12
B. N
et $
107.
00; w
ith 3
-w
ay I2
TR
XB
,N
et $
138
Add
-on
E -
V M
AR
QU
IS:"
mat
chin
g al
ong
-the
-w
all c
ount
erpa
rt o
f the
popu
lar
Aris
tocr
at. R
espo
nse
dow
n to
40
cps.
With
SP
12B
, Net
$98
.00;
with
3 -
way
12T
RX
B, N
et$1
29
Add
-on
E -
V R
EG
AL
III
...su
per
-com
pact
, spe
cial
ly d
esig
ned
syst
em w
ith ta
ilore
dco
mpo
nent
s to
giv
e en
hanc
ed r
ange
and
pur
ity o
f ton
ew
ith le
ast l
oss
of e
ffici
ency
. Doe
s no
t req
uire
hig
hpo
wer
ed a
mpl
ifier
, Net
$14
7.50
Adr
i-er
nE
-V
EM
PIR
E*.
..di
rect
rod
iato
r K
lipsc
h-lic
ense
d lo
wbo
y en
clos
ure
tai-
lore
d fo
rus
e al
ong
-the
-w
all o
rin
corn
er. S
moo
th,
exte
nded
bos
s re
spon
se. W
ith E
lect
ro-V
oice
15T
RX
B3
-way
spe
aker
, Net
$17
8
`sys
tem
s sh
own
are
but a
few
of
the
mul
titud
e of
k -
V c
orn-
bina
tions
fou
nd in
eve
ry p
rice
cla
ss. A
sk y
our
deal
er o
rw
rite
Ele
ctro
-Voi
ce f
or in
form
atio
n on
the
indu
stry
's m
ost
Lui
iiple
te li
ne o
f hi
gh f
idel
ity s
peak
ers
and
encl
usur
es.
Add
-on
the
new
E -
V C
OR
ON
ET
'..tr
ue, b
alan
ced
high
fide
lity
repr
oduc
tion
in e
xtre
mel
y sm
all e
cono
mic
al s
pace
-sa
ving
form
: onl
y 10
inch
es o
fw
all s
pace
req
uire
d.C
ompl
emen
ts A
risto
crat
,M
arqu
is, B
aron
et o
r
com
para
ble
spea
ker
opte
m. W
ith 5
P13
88
-inch
spea
ker,
res
pons
e do
wn
to 7
0 cp
s., N
et $
65.0
0cr
sont
opv
IA...
Ot.
5000
e.n
ei
I ..0
1kW
it' d
river
,4,
111.
12.V
U, o
r 00
0 -o
nR
EG
AL
IA. N
et $
103
Add
-on
STE
RE
ON
IA
The
all
-new
Ele
ctra
-V
oice
spe
aker
sys
tem
that
sol
ves
your
spa
ce p
robl
em-s
aves
you
mon
ey. W
here
spa
ce d
oesn
't pe
rmit
you
to o
dd a
sec
ond
full
-ran
ge s
peak
er,
a S
tere
onis
the
answ
er.
It's
com
pact
,be
caus
e th
e S
tere
on r
epro
duce
s on
ly th
ose
froa
rpt,n
rip, n
oprI
nfq
for
tte/P
n R
uss
belo
w10
0 cp
s do
es n
ot c
ontr
ibut
e to
the
ster
eo
effe
ct ..
. so
bass
from
bot
his
han
dled
hvyn
iirth
rnol
okth
e ac
cess
ory
XX
3 S
tere
on C
ontr
ol F
ilter
.(F
ines
t E V
mid
bas
s, tr
eble
and
hig
h fr
e-qu
ency
com
pone
nts
give
sm
ooth
res
pons
efr
om 3
00 to
19,
000
cps.
)
ST
ER
EO
N IA
-for
sys
tem
s of
nor
mal
effi
-ci
ency
, Net
$99
.50
X X
3 S
TE
RE
ON
CO
NT
RO
L F
ILT
ER
, Net
$30
ELE
CT
RO
.VO
ICE
, IN
C.,
BU
CH
AN
AN
, MIC
HIG
AN
For
emas
t in
Ele
ctro
-Aco
ustic
s-M
icro
phon
e, F
hono
.Cor
-tr
idge
s, H
igh
-Fid
elity
Loud
spea
kers
and
Enc
losu
res.
itubl
ic A
ddre
ss S
peak
ers,
Mar
Ae
Inttr
umen
ts, L
VI P
rofe
ssio
nal E
lect
roni
c In
stru
men
ts a
nd M
ilita
ry M
ater
iai.
STE
P-U
PT
O T
HE
FIN
EST
EL
EC
TR
O-V
OIC
EST
ER
EO
'S S
TA
ND
AR
D
-11I
rif this is your preseitt ur proposed speaker system
.4,1
1111
1
0000
00
0000
00
step
one
you
need
the
LuLa
llyco
mpa
tible
EzN
i ST
ER
EO
CA
RT
RID
GE
Tho
usan
ds a
lread
y in
use
pro
veit
play
s al
l rec
ords
bet
ter:
une
xcel
led
for
ster
eo; s
uper
ior
even
to y
our
pres
ent
cart
ridge
for
mon
aura
l. H
ighe
st v
erti-
cal a
nd h
oriz
onta
l com
plia
nce.
Bes
tch
anne
l sep
arat
ion:
ove
r21
.)db
betw
een
chan
nels
. Fla
ttest
res
pons
es:
flat b
eyon
d au
dibi
lity
to R
IAA
cur
ve.
Hum
and
rum
ble
are
far
belo
w a
nym
agne
tic c
ortr
idae
. Tw
o ce
ram
ic e
le-
men
ts d
eliv
er p
reci
se R
IM c
urve
with
no b
urnt
Exc
lusi
ve E
-V
Bui
lt-in
Rum
ble
Sup
pres
sor
allo
ws
reco
rd c
hang
er u
sefo
r st
ereo
..7 m
il re
plac
eabl
e (d
iam
ond
Or
sapp
hire
) st
ylus
Is W
ent s
ine
...gi
ves
bette
r re
prod
uctio
n, lo
nger
reco
rd w
ear.
The
E -
V T
otal
ly C
ompa
tible
Ste
reo
Car
trid
geIs
the
Indu
stry
's s
tand
ard.
Cho
ose
the
mod
el to
fit y
our
need
s:M
OD
EL
21D
-Ste
reo
with
.7 m
il D
ia-
mon
d S
tylu
sN
et $
19.5
0M
OD
EL
26 D
ST
-Dua
l Sty
lus
Tur
nove
rfr
om .7
mil
Dia
mon
d S
tere
o to
3 m
ilS
apph
ire M
onau
ral..
Net
$22
.50
or th
eE
-V
'Mes
hy S
tere
o C
artr
idge
MO
DE
L 2I
MD
-Ste
reo
with
.7 m
il D
ia-
mon
d S
tylu
sN
et $
19.5
0M
OD
EL
26M
DS
T-D
ual S
tylu
s T
urno
ver
from
.7 m
il D
iam
ond
Ste
reo
to 3
mil
Sap
phire
Mon
aura
l. .
Net
$22
.50
The
n ch
oose
a s
econ
d am
plifi
er a
ndpr
e -a
mpl
ifier
. If t
his
is y
our
initi
al h
igh
fidel
ity s
yste
m, s
tart
with
any
ste
reo-
phon
ic d
ual a
mpl
ifier
-pr
eam
plifi
er.
Pla
y m
onau
rally
unt
il yu
u ad
d a
seco
ndsp
eake
r fa
r st
ereo
.
.®
EIE
CT
IO.V
OIC
E, I
NC
., S
tle.N
AN
AN
, MIL
NI,A
N
Fam
e. in
Elo
ctro
.Aco
olic
s-M
icro
phon
e. P
hinn
arC
arfr
idge
s, N
igh
-Fid
elity
loud
spea
kers
and
Enc
,
Pub
lic A
ddre
ss S
pank
ers,
Mar
ina
Inst
rum
ents
, EV
I Pro
-fe
ssio
nal e
lect
roni
c In
stru
men
ts a
nd M
ilita
ry M
ater
ial.
4 -w
ay 1
2 -in
chsp
eake
r sy
stem
cost
ing
betw
een
$200
and
$30
0su
ch a
s th
eE
-V
Duc
hess
IVE
(Net
$29
2)
Add
-on
the
E -
V
DU
CH
ES
S IV
E
Une
xcel
led
for
purit
yof
tone
and
ran
geth
roug
h hi
ghly
dev
el-
oped
4 -
way
driv
ersy
stem
, Sup
er -
effi-
cien
t, sm
ooth
re-
spon
se th
roug
h us
eof
diff
ract
ion
horn
sto
giv
e w
ide
ster
eolis
teni
ng a
rea;
bos
sis
esp
ecia
lly e
xten
d-ed
in r
ange
thro
ugh
EN
Pha
se -
Load
ing
prin
cipl
e w
ith 1
2"dr
iver
mou
nted
low
and
at r
ear
of e
nclo
-su
re. C
ompa
res
inpe
rfor
man
ce to
cor
-ne
r ho
rns.
Net
$29
2
3 -w
ay s
peak
er s
yste
m c
ostin
g be
twee
n)3
00 u
vJ )
1E1
such
as
the
E -
V M
arqu
is II
I(N
et $
303)
or th
e E
-V
Aris
tocr
at II
I(N
et $
3121
II
Add
-on
the
E -
V
AR
IST
OC
RA
T II
IIII
-AR
IST
OC
RA
T delu
xelip
sch-
licen
sed
sep-
arat
e 3
-way
loud
-sp
eake
r sy
stem
for
smoo
th, e
ffici
ent
wid
e -r
ange
rep
ro-
'duc
tion.
Use
s fo
lded
rn th
roat
in c
on,
tfu
rnitu
re p
iece
plea
sing
pro
per
s. T
he w
alls
of t
hein
g ro
om a
nd th
ern
er fo
rm th
e la
rge
horn
mou
th r
equi
red
for
low
est r
ange
response.
Diff
ract
ion
ins
intr
eble
and
ry h
igh
rang
e in
-to
bes
t ste
reo
over
Wid
est l
iste
ning
are
a.
Nut
$31
2
Add
-on
the
E -
V
MA
RQ
UIS
III
Com
pani
on p
iem
atch
es A
risto
crIII
. Use
s sa
me
driv
syst
em. D
esig
ned
oper
ate
optim
umly
alon
g -t
he -
wal
l po
tion
whe
re a
car
is n
ot a
vaila
ble.
Net
$30
3
4 -w
ay 1
5 -in
ch
cost
ing
betw
een
$325
and
$37
5su
ch a
s th
eE
-V
Car
lton
IV(N
et $
359)
Add
-on
the
E -
V
CA
RLT
ON
IVD
elux
e ve
rsio
n of
the
Duc
hess
IVE
in s
mar
t,ha
ndso
me
low
-bo
yde
sign
; har
mon
izes
grac
eful
ly w
ith m
any
mod
ern
furn
ishi
ngm
odes
. A c
ompl
ete
Pha
se -
Load
ed S
ys.
tem
, affo
rdin
g un
-us
ual b
ass
resp
onse
with
sm
ooth
, res
o-na
nce
-fre
e ch
arac
ter-
istic
s. In
clud
es d
elux
e15
-in
ch in
dire
ct b
ass
driv
er 4
-w
ay c
ompo
-ne
nts. N
et $
359
4 -w
ay c
orne
r10
inch
spu
tum
syst
em c
ostin
gbe
twee
n$3
25 a
nd $
375
such
as
the
E -
V C
entu
rion
IVE
(Net
$36
5)
3 -w
ay 1
5 -in
chap
e el
m s
ytirm
cost
ing
betw
een
$375
and
$40
0su
ch a
s th
e ne
wE
-V
Reg
ency
III
(Net
$39
3)
step
two
Add
-on
the
E -
V
CE
NT
UR
ION
IVE
New
com
plet
e 4
-way
syst
em in
corp
orat
ing
all d
esig
n fe
atur
es o
fth
e m
agni
ficen
t E -
VG
eorg
ian,
but
on
asm
alle
r sc
ale.
Use
sK
lipsc
h "K
" fo
lded
horn
with
E -
V d
elux
e12
-in
ch in
dire
ct -
radi
-at
or s
peak
er s
yste
m,
(I2W
Kdr
iver
, MT
-30
coa
xial
mid
-bo
ssan
d tr
eble
ass
embl
y,13
5 V
HF
driv
er a
ndX
336
cros
sove
r). R
e-sp
onse
from
30
cps
to b
eyon
d au
dibi
lity.
Net
$36
5
Add
-on
the
E -
V
RE
GE
NC
Y II
I
The
ver
satil
e R
egen
cyIII
del
uxe
sepa
rate
3 -w
ay s
yste
m a
llow
sop
erat
ion
in th
e co
r-ne
r fo
r fu
ll ba
ss e
ffi-
cien
cy o
r al
ong
the
wal
l for
con
veni
ence
.P
ower
ful 1
5 -in
ch b
ass
driv
er c
ross
es o
ver
at80
0 cy
cles
per
sec
-on
d to
diff
ract
ion
-ty
pe tr
eble
and
ver
yhi
gh fr
eque
ncy
com
-po
nent
s to
giv
e m
axi-
mum
dis
pers
ion
and
full
ster
eo e
ffect
.
Net
$393
4 -w
ay c
orne
rIf
inch
rror
'^'
syst
em c
ostin
gbe
twee
n$4
00 a
nd $
480
such
as
the
E -
V C
ardi
nal I
V(N
et $
425)
Add
-on
the
E -
V
CA
RD
INA
L IV
Aut
hent
ic E
-V
Klip
sch
"K"
horn
not
ed fo
rde
ep fu
ndam
enta
lba
ss r
ange
; com
ple-
men
ted
by d
iffra
ctio
npr
inci
ple
in c
oaxi
alm
id -
bass
and
treb
ledr
iver
ass
embl
y. V
ery
high
freq
uenc
ies
in.
sure
raa
lism
ove
rbr
oade
st li
ving
roo
mar
eas. N
et $
425
or a
ltern
ate
step
two
AD
D-O
N E
-V
ST
ER
EO
N I
IIT
he a
ll -n
ew E
lect
ro-V
oice
spe
aker
sys
tem
that
sol
ves
your
spa
ce p
robl
em-s
aves
you
mon
ey. W
here
sam
e do
esn'
t pet
tnil
yuu
to u
JJ a
sec
ond
full
-ran
ge s
peak
er,
a S
tere
on is
the
answ
er. I
t's c
ompa
ct, b
ecau
se th
e S
toro
on r
epro
duce
s on
ly th
ose
freq
uenc
ies
NE
ED
ED
for
ster
eo (
bass
bel
ow 3
00 c
ps d
oes
not c
ontr
ibut
e to
the
ster
eo e
ffect
... s
o ba
ss fr
om b
oth
is h
andl
ed b
y yo
ur P
RE
SE
NT
full
-ran
ge s
peak
erth
roug
h th
e ac
cess
ory
XX
3 S
tere
on C
ontr
ol F
ilter
),
Ste
reon
s ha
ve th
e fin
est E
-V
mid
-ba
ss, t
rebl
e an
d hi
gh fr
eque
ncy
com
pone
nts.
(Fre
quen
cy r
espo
nse,
300
to 1
9,00
0 cp
s).
ST
ER
EO
N Il
l for
hig
h ef
ficie
ncy
syst
ems
Net
$12
9.50
XX
3 S
TE
RE
ON
CO
NT
RO
LN
et $
30.0
0N
OT
E: A
ll E
-V
Sys
tem
s al
so a
vaila
ble
in li
med
oak
or
wal
nut f
inis
hes.
4 -w
ay c
orne
r.r
ent,n
.sy
stem
cos
ting
betw
een
$480
and
$60
0su
ch a
s th
eE
-V
Geo
rgia
n 60
0(N
et $
490)
Add
-on
the
E -
V
GE
OR
GIA
N 6
00U
tiliz
es s
ame
horn
cons
truc
tion
and
driv
er c
ompl
emen
t of
Car
dina
l IV
enc
lose
dby
bea
utifu
l con
tem
-po
rary
hou
sing
func
-tio
nally
sty
led
byR
ober
t W. F
uldn
er.
Net
$49
0
4 -w
ay c
orne
r 18
-in
ch s
peak
ervo
nsu
ch a
s th
e in
com
para
ble
E -
V P
atric
ian
(Pat
ricia
n IV
Tra
ditio
nal,
$970
;P
atric
ian
600
Con
tem
pora
ry,
$819
Net
t
Add
-on
the
inco
mpa
rabl
e
PA
TR
ICIA
NW
orld
's lu
ryes
l, m
ost d
elu.
ke lo
ud-
spea
ker
syst
em fo
r th
ose
disc
rimi-
natin
g lis
tene
rs w
ho d
eman
dul
timat
e to
nal p
erfe
ctio
n. T
heep
itom
eof
styl
eco
mbi
ned
with
pea
k pe
rfor
man
ce fo
rth
eul
timat
eill
usio
nof
real
ity.
Ava
ilabl
e as
the
Pat
ricia
n IV
in
trad
ition
al s
tylin
g.N
et $
970
Pat
ricia
n 60
0 in
Ful
dner
-des
igne
d"'m
ultip
olar
yN
et $
819
Spe
cial
mod
els
avai
labl
eto
cust
om -
finis
h sp
ecifi
catio
ns ..
. at
high
er p
rice.
Sys
tem
s sh
own
are
but a
few
of t
hem
ultit
ude
of E
-V
com
bina
tions
foun
d in
ever
y pr
ice
clas
s. A
sk y
our
deal
er o
rw
rite
Ele
ctra
-V
oice
for
info
rmat
ion
onth
e in
dust
ry's
mos
t com
plet
e lin
e of
high
fide
lity
spea
kers
and
enc
losu
res.
- - Circle 45-01 on inquiry form page 73
1
Every part of every Collaro changer
is precision -engineered to meet the rigid demands of Stereo
The new stereo records require a higherstandard of performance from your recordchanger than do standard LP's because stereocartridges are extra -sensitive to noise. That's why.in planning your stereo system, you begin with theCollaro. Every part of every Collaro changer isprecision -engineered to meet the rigid qualitydemands of stereo.
The motor (see A above) is dynamically bal-anced, so rigidly mounted that wow and flutterspecifications are superior to any changer.
The spindle assembly (B) reflects this pre-cision quality in every part. The spindle itselfis micro -polished for complete smoothness.
The sensitive velocity trip mechanism (partshown in C) has been designed so that the
Circle
changer can trip at extraordinary light trackingpressures.
The exclusive Collaro transcription -type tonearm (D) with the new plug-in head (E) is de-signed to eliminate all resonances in the audiospectrum. The new four -pin head - the only highfidelity changer with this feature - provides theultimate in noise -reduction circuitry.
There are three Collaro changers ranging inprice from $38.50 to $49.50. No matter which youselect, you're sure to start your system off rightwhen you choose Collaro - the turntable thatchanges records.
For new Collaro catalog write to Dept. ET -9.Rockbar Corporation, Mamaroneck, New York.46-01 on inquiry form page 73
Rockbaris the American
sales representativefor Collaro, Ltd.
46 ELECTRONIC TECHNICIAN Stereo, 1959
The Meaning of Stereo
Stereo means a new horizon of electronic enter-tainment. A refreshing treat is in store for thethousands of audio enthusiasts and millions of musiclovers who have made the term High Fidelity abyword in American homes.
Stereo-short for stereophonic sound-adds thedimension of depth to our listening pleasure. It en-hances the sense of realism in sound reproduction.
How Stereo Works
Just as our eyes perceive depth by each eyeseeing a particular scene slightly different from theother, so our ears detect depth in sound.
In the conventional monophonic sound system,a single one -channel program is reproduced. Eventhe use of two speakers does not provide a realsense of depth in monophonic sound because thesound reaching the ears does not have the informa-tion needed for the stereo effect.
With stereo, two (or more) spaced microphonesrecord the program material in separate channels.Each channel recording is different, in an amountdetermined by the relative intensities and locationof the program source or sources in relation to themicrophones.
When the program recordings are picked up andreproduced through separate amplifier -speakerchannels, and a greater portion of the sound fromeach channel reaches each ear, respectively, in amanner similar to the original sound reaching themicrophones, depth is perceived aurally.
Equipment for StereoStereo on magnetic tape came first. Recording
multiple tracks on a single tape enables the twosound channels to be kept apart and reproducedthrough separate electronic channels in the samemachine.
With disc recordings in very wide use, the in-dustry sought a practical means for producing andreproducing from stereo records. To the notablecredit of industry engineers, a means was developedfor recording two channels of sound in a singlerecord groove. The two channels are picked up bya single needle in the new stereo cartridges. Basi-cally, this is accomplished by the groove impartingup-and-down motion to the needle, in addition tothe conventional side -to -side.
The electrical signals from the cartridge arepassed through two preamp/amplifier channels, andreproduced in two speaker systems placed apart ina manner which provides the stereo effect.
Stereo has even entered broadcasting, one soundchannel being broadcast on FM, the other on AM.For the future, tuners may be adapted to receivemultiplex signals; that is, two channels on one FMstation.
Stereo-Now!Stereo is no longer a drawing -board concept. A
wide selection of stereo equipment from manymanufacturers is available today at reasonable cost.Good equipment will not only give you stereo . . .
it will give you stereo high fidelity.If you presently own good monophonic equip-
ment which you do not wish to discard, units forthe second channel can be added for stereo. Forthe many people who are not adept at makingelectronic hookups, the local electronic servicetechnician has the know-how and equipment tomake the conversion.
If you are starting afresh, a wide range of attrac-tive equipment, specially designed for stereo, isyours to select.
A rapidly growing number of stereo discs arebecoming available.
Get more listening pleasure. Get stereo!
ELECTRONIC TECHNICIAN Stereo, 1959 47
Fig. 1-Early single groove stereo discs hada vertical and horizontal axis. The 45/45Westrex system, shown on the right, main-tains the same relative position between thetwo axes, but both axes are rotated 45°, as aunit, to obtain symmetry of movement.
Stereo Discs
Two Channels
In One Groove
Fig. 2-A. Right channel modulates outer side wall. Stylus travels up to the left and down tothe right. B. Inner side war is modulated by the left channel. Stylus travel is up to the rightand down to the left. Groove center is always midway between both walls.
64
64
UNMODULATED ORREFERENCE GROOVE
.1 REFERENCE Iy CENTER y
ii
INNER SIDEWALL
GROOVE CENTER
OUTER SIDEWALL
13'
3
UNMODULATED ORREFERENCE GROOVE
I REFERENCECENTER y
RIGHT HANDINFORMATION
.41-r-- ONOUTER
SIDE WALL
6 4
LEFTHANDINFORMATION
ON
INNERSIDE WALL
1
12 30 6 4
I
OUTER SIDEWALL
GROOVE CENTER
INNER SIDEWALL
The intelligence in the modernmonophonic LP record is pressedinto the groove in such a manner asto enable a cartridge whose stylus ismoving in a horizontal plane to re-cover the information on playback.Older forms of records, now obso-lete, required the playback stylus tomove up and down. London Recordsused a combination of these twomovements for monogroove stere-ophonic recording. Demands on thecartridge for equally high compli-ance in both the horizontal and ver-tical direction presented difficultmechanical problems. Some of theseproblems were alleviated whenWestrex introduced the 45/45 sys-tem. While the 90° relationship be-tween the vertical and horizontalaxis was maintained, both axes wererotated 45°, as shown in Fig. 1.
Symmetry of movement was thusachieved for each channel.
In this system the stylus is forcedto travel a diagonal path for eachchannel. The right hand channelmodulates the outer side wall of thegroove, which means that the stylushas to travel up to the left and downto the right as shown in Fig. 2A.Part B of this figure shows that forthe left hand channel, which modu-lates the inner side wall, the stylusmust travel up to right and down tothe left. In both cases the side wallwhich is not modulated remainsstraight. (The groove traverses aspiral path. To simplify drawingsand text the unmodulated groove ispresented as a straight line which isessentially true for the relationshipbetween the cutting stylus and thegroove. The concept of what actually
48 ELECTRONIC TECHNICIAN Stereo, 1959
THE STEREO RECORD
Westrex 45/45Diagonal Motion
Horizontal ComponentsVertical Components
Mechanical PhaseIn -Phase
Vertical MovementOut -Of -Phase
Horizontal Movement
Electrical PhaseIn -Phase
Horizontal MovementOut -Of -Phase
Vertical Movement
Movement IndicatorsGroove Width
Vertical DisplacementGroove Center
Lateral Displacement
happens is not affected thereby.) Asthe stylus rides up and down, thegroove becomes narrower and widerrespectively, and as the stylusmoves back and forth the centerline of the groove moves according-ly. It is well to keep in mind thatthe needle point is always in thegroove center, and that the needlealways contacts both sidewalls.
This is true, even though thereare two different signals impressedin each groove and one sidewallmay have many more curves thanthe other; and the needle may traceout circles, and ellipses; if the sty-lus is tracking properly it mustmaintain contact with both sidewallsat all times.
Contrary to some published state-ments the stylus cannot trace out acorkscrew motion. All motion isconfined to the vertical plane whichcuts the record in half along its di-ameter. Vertical, horizontal and di-agonal stylus motions are all on thisplane. The stylus cannot, or at leastis not supposed to, travel eitherbackwards or forwards. This ofcourse applies to actual stylus mo-tion. Relative motion between thegroove and stylus-if projected in adrawing-could in some cases ap-pear as a corkscrew.
At any given instant the stylusis in one position only. This position"defines" both walls. The questionnow is what happens to the styluswhen both channels are differentlymodulated at the same time. Fig. 3illustrates how the stylus motion andrelative groove width, at any giveninstant, corresponds to the differentforces at work. When both chan-nels are pushing up at the sametime and the same amount, thestylus will travel straight up.
This in -phase motion can also(Continued on page 96)
t/I\ONLY
CHANNEL AMODULATED )
REFERENCE
/1\sNtONLY
CHANNEL B(MODULATED
REFERENCEGROOVE
st%
BOTH
\ CHANNELS AeBMODULATED
Fig. 3-Stylus position on disc for various conditions of modulaticn. The stylus may move upor dowr, and right or left depending upon the information impressed on each channel.
Fig. 4-Top. Pinching and expanding groovescause stylus to rise and fall. Straight centerline indicates that there is no lateral motion.Bottom. Equal size grooves allow the stylusto ride without vertical displacement. Curvedcenter line shows lateral motion.
UNMCDULATED ORREFERENCE GROOVE
i6NERSIDE:PALL
4
OUTERSIDESIDEWALL
3
31
OUTERSIDEWALL.4 --
GROOVE CENTER
Rg. O.-Combination of both lateral andvertical displacement at the same time, andvarying conditions from one instant to thenext give the groove a shape that seeminglycannot be tracked. It can-see text!
UNMODULATED ORREFERENCE CROOVE
Y
t
' INNER SIDE WALL
2 3 66
OUTERSIDEWALL
6 31
6
CENTER.3ROOVE
5 13 I6
ELECTRONIC TECHNICIAN Stereo, 1959 o:
Fig. 1-Switch and outlets on master con-trol box can turn the entire system on oroff. It is possible to have the switch on anautomatic record player perform this func-tion by inserting it in the line at point X.
INPUTCHANNEL A
INPUTCHANNEL B
COMMON
APPROX.MEG
OUTPUT CHANNEL A
110.
OUTPUT CHANNEL B
APPROX.I MEG
Fig. 2-Dual linear controls, each wired inreverse order can equalize the sound fromboth channels without changing the overallvolume level. As one level goes up the othergoes down.
Fig. 3-The SPDT switch enables the listenerto change from stereo to monophonic witheither channel fed into both amplifiers andspeaker systems. The stereo channel revers-ing switch also determines which signalchannel is used for monophonic purposes.
Master Control For StereoOne -Knob Control For Both Channels.
Getting stereo is one thing; con-trolling it to give its best is another.All of the three potential sources,radio, tape, or disc may be present,but the program must be balanced,both tonally and stereophonically,and at the right listening level forbest enjoyment. The control unitmay be part of the preamplifier, ora separate but complete master con-trol center. The master control mayconsist of passive and amplifier cir-cuits, or passive circuits only withjust switches, plugs, and other con-trols. It may also contain equaliza-tion and other matching networks.The import of the question, "Do wewant more or fewer knobs?" is nowmultiplied by two, and then some.
At first thought it may seem asthough the control center would as-sume monstrous proportions, butactually compact units about 1/3rdthe size of a tuner are available, orcan be constructed. However, theamount of electrical accomplish-ments and added convenience thislittle box provides are so great thatthey may spell the difference be-tween selecting a stereo program inthe same manner as an ordinaryprogram from a table radio by justflicking a switch, or selecting an at-tack of stereo knobitis.
It is possible to perform most orall of the following functions, witha properly designed control box, andwith minimum effort:
1. Power-Turn the complete sys-tem on or off.
2. Balance-Or focus, equalizeoutput from both channels,without changing volume.
50
3. Volume-Control volume levelwithout losing balance.
4. Stereo-Normal stereo programin, normal stereo out.
5. Reverse-Reverse stereo pro-gram in, normal stereo out; orvice versa.
6. Monophonic-(A) Monophonicprogram on one channel only.(B) On both channels in par-allel for dual power, and use ofboth speaker systems. (C)Stereo program in, monophonicout of one or both channels.
True, these are a lot of functions,but once the system is installed,there should be no unusual diffi-culty or need for excessive knobhandling. There are as many if notmore controls and adjustments on aTV set. Once the system is in oper-ation it is only necessary to flip oneswitch to turn on the system, selectthe program, and adjust the volumecontrol.
The control box may also providetone controls, loudness contour con-trols, rumble filter and a blend con-trol. So far as the consumer isconcerned, this is as far as he has togo, but the technician must considera mass of additional detail. Like anycontrol center in any mechanical orelectrical system, connections to thevarious components to be controlledmust be provided. To obtain the de-sired functions just described thefollowing jacks or connectors shouldbe available, preferably in the rearof the unit.
1. AC power outlets2. Audio outputs3. Tuner Inputs
4. Tape Inputs5. Phono Inputs
Power OutletsThe power outlets and associated
wiring should have sufficient watt-age ratings to safely handle the load.If all the a -c power is fed throughthe switch and outlets on the con-trol box, as shown in Fig. 1, thenall the components can be controlledby one switch. It is also possible toarrange a system in which the rec-ord changer can shut off all equip-ment after the last record is played.Usually no more than two outletsare required because the amplifierand other components have poweroutlets which can be used. It mayalso be desirable to have a pilotlight in the control box.
Balance & VolumeIt would seem ideal in a stereo
system to gang almost all the simi-lar controls in both channels; equal-ization, volume, loudness, and tone.This makes for simplicity. If thevolume and loudness controls arestacked, a balance or focus controlis needed. Although a 1 db changein level is difficult to detect on asingle channel, it does make a no-ticeable difference in stereo. This isa good reason for checking balancewith a known stereo recording,while sitting in a desirable position.Separate test and level adjustmentsof first one channel and then theother is hardly adequate.
Because stereo balance is fairlycritical, the balance control may
(Continued on page 94)Circle 51-01 on inquiry form p. 73 ---)11'
ELECTRONIC TECHNICIAN Stereo, 1959
THANK THE KEEN -EYED SNOOPERAs little as .0035 of an inch off in the dimensions of this Utah speaker basket-and a rejecthits the bin! At Utah the quality of final performance in the speaker you buy is a jealouslyguarded value. If you could visit our Huntington plant you'd probably agree with AcePhotographer Lieberman that Utah speakers prove rejection is the foundation of perfection.
Pre -assembly, plating, coil winding, wiring . . . at every step down the production linestand the "Leen-eyed snoopers." They search ruthlessly for the tiniest defect that couldmar, even minutely, the response performance of a Utah.
Make certain your next speaker is a Utah. Know that your sound will be as perfectlyreproduced as human skills, controlled by rigid inspection, can produce.
See the Utah Custom Line: a quality speaker for every system need.
* ARCHIE LIEBERMAN,famous newsmagazine*photographer, was given thisassignment on a recentUtah plant tour: Photographthe essence of Utah qualityas you see vt. The photoshown here is the result.(*Look, Life, Time, Pageant,Parade, Newsweek andmany others)
!o-tuti ezub dad j the, &Auk eitoit6Send for the big Utah Catalog. Dept. 2, UtahOFML:\ EEE0 Vir Radio & Electronic Corp., Huntington, Ind
Converting to StereoPresent Record Players Can Accept The New Stereo Cartridges.
Probably the most critical portionof the work is in the installation ofthe stereo cartridge. In most casesit will be necessary to run a newlead through the pickup arm toaccommodate the 3rd or 4th termi-nal. In anticipation of the conver-sion job, many new cartridges arepackaged with the necessary termi-nals, wire, spacer washers, andscrews. Conversion kits are alsoavailable for the various recordchangers and turntables. Tone armshaving plug-in cartridge holders,equipped with only two terminalspresent a bit of a mechanical prob-lem if the plug-in feature is to bemaintained.
Most conversion kits solve thisproblem by providing a new 3 or4 -terminal fitting and shell. How-ever, in some cases it is necessaryto dismantle the tone arm to assem-ble these new parts. It may be pos-sible to do this without upsettingtoo many adjustments on somechangers. It is therefore importantthat no more work or dismantlingbe accomplished than is absolutelynecessary. Once a changer tone armis worked on, it becomes necessaryto check stylus pressure, set down,trip mechanism and arm elevationduring the change cycle. In the ab-sence of a conversion kit it is pos-sible to fit a flat piece of metal intothe rear portion of some cartridgeshells, where the terminals are, insuch a manner as to contact another
Fig. 1-To establish the second channel forstereo disc programs, it is necessary to add asecond amplifier end speaker, and to changethe cartridge The control box is optional.
52
flat piece of metal which has to beinstalled on the tone arm, as shownin Fig. 2. This is tricky, and can beavoided by sacrificing a little mo-bility. Run the third wire directly tothe cartridge. Leave enough slack todisengage the shell, and to slide thewire clip on or off the cartridgeterminal.
Still another problem manifestsitself, if for some reason it is desiredto plug in a two -terminal shell andits monophonic cartridge after thearm has been wired for stereo. Oneof the hot leads for the stereo car-tridge will have to be grounded for
Fig. 2-To convert a two -pin shell to accepta stereo cartridge, it is necessary to pro-vide a connection for the added terminals.
the monophonc cartridge. Lookingat the terminal end of a stereo car-tridge with the stylus pointingdown, the pin on the right is for theright channel, and the pin on theleft is for the left channel. The cen-ter terminal or terminals go toground. In the four -pin cartridgethe two center terminals may ormay not be tied together dependingupon wiring and electrical require-ments. Since the monophonic car-tridge utilizes the two outer termi-nals, what now constitutes one hotterminal for one stereo channel willhave to become a ground connectionfor the monophonic cartridge. Itthen becomes necessary to install aSPDT switch as close to the car-tridge as possible. The farther awaythis switch is installed, the greateris the possibility of introducing hum.All this of course points up the factthat the more functions that are
Fig. 3-To revert back to a monophonic shell,once a conversion has been accomplished, itis necessary to provide a hum -free switch.
added, and the more complex theinstallation becomes, the noisier thesystem is going to be. If the mono-phonic cartridge is installed in astereo shell, it can be wired to anappropriate end terminal and thecenter ground terminal. Keep theinstallation as simple as possible.Except for very rare occasions, thereshould be no need to switch backto a monophonic cartridge once astereo unit is installed.
If the two elements of the stereocartridge are connected in parallel,it will become fairly insensitive tovertical stylus movement and mayeven render superior performanceon a monophonic system. This isanother good reason for installing astereo cartridge as soon as possibleeven before the additional amplifierand speaker are obtained. Also,some monophonic cartridges coulddamage the new stereo discs.
Impedance matching and ampli-fier input sensitivity are important,and require the same care and con-sideration as before. As a generalrule, the former high -impedanceamplitude -sensitive ceramics re-quire still higher input impedanceto avoid loss of bass, but in mostcases do not require preampli-fication or equalization. The low-impedance, velocity -sensitive mag-netics, moving coil, moving iron andvariable reluctance types should beplayed through a preamplifier andequalization circuitry. Both typesgive a smaller output voltage toeach stereo amplifier. In most casessufficient reserve power is available.
(Continued on page 58)Circle 53-01 on inquiry form p. 73)
ELECTRONIC TECHNICIAN Stereo, 1959
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MOVINGCOIL
VARIABLERELUCTANCE
or MOVING IRON
Fig. 1-The stereo cartridge has two elements set at right angles ramie, moving coil, moving iron or other conventional types. Cart -to each other, and 45° from the vertical. The elements may be ce- ridges may have 3 or 4 pins. They can be used on monophonic discs.
The Stereo CartridgeComplex Mechanical Forces Work On Cartridge Having
One Stylus, Two Elements, Three Or Four Terminals.
STEREO CARTRIDGEVelocity Sensitive
Moving CoilMagneticVariable Reluctance
Amplitude SensitiveCeramic
OutputLevels
HighLow
ImpedanceHighLow
Terminals3 pin4 pin
PhasingMechanicalElectrical
Rumble SuppressionMechanicalElectrical
The stereo cartridge is anotherexample of modern ingenuity. Fora long time the industry waswrestling with gigantic monophoniccartridge problems dealing with fre-quency response, output character-istics, compliance, stylus pressure,undesirable resonance conditions,hum and noise suppression, etc. Somuch work was accomplished thatno longer was it valid to think in
54
terms of inherent characteristics.Inherent characteristics have beencompensated for to the point wherea normally non-linear device ismore linear than some units whichnaturally have good linear qualities.This is true for the many othercharacteristics; so much so, thateach cartridge should be evaluatedon an individual basis rather thanaccording to type.
Before the engineers could claimvictory over all of the problems inmonophonic cartridge design, stereostuck its two -element head into thelaboratory.
The problems now multiplied ata rate that was pretty much in stepwith the square law. Twice as manychannels meant four times as manycomplexities.
Several new parameters appearedsuch as separation between chan-nels, uniform and equal output fromboth channels, and susceptibility tovertical rumble. The problems ofdistortion and intermodulation dis-tortion have yet to be resolved100%. In the early days the car-tridge people needed a test stereodisc. The disc people needed a stereocartridge. Because the final resultsdepended on the quality of bothitems, and because of an absenceof a standard, it looked as thoughthis bottleneck would last a longtime.
However, once the stereo ball
started to roll, various segments ofthe high fidelity industry began tomove at once. Now in somethingbetter than record time, the stereocartridge is a reality, as are thestereo disc and the components toplay them. Except for three orfour terminals the outside appear-ance of the cartridge is conven-tional. Internally, almost all stereocartridges have another elementadded. The two elements are ar-ranged so that they are at a 90°angle from each other, but at a 45°angle from the vertical, as shown inFig. 1. The elements used may beany of the conventional types, mov-
Fig. 2-Vertical stylus displacement isa result of in -phase mechanical forces.
EIECTRONIC TECHNICIAN Stereo, 1959
ing coil, magnetic, crystal, etc. Itmay even be possible to use a com-bination of different elements. Be-cause both elements in the cartridgeare placed on a 45° angle, they aresensitive, to a degree, to both ver-tical and lateral movements. The upand down displacement is a vectoralsum of in -phase mechanical motionas shown in Fig. 2. Since it is speci-fied that the signal must be out ofphase for this condition, either oneelement or its leads must be re-versed. This is accomplished in themanufacturing process. Fortunately,this also satisfies the requirementthat an in -phase signal be derivedfrom a horizontal motion. Fig. 3 il-lustrates relative output voltages fordifferent stylus motions.
This also happens to be a verydesirable feature for monophonicplayback. By connecting both ele-ments in parallel, the cartridge be-comes insensitive to vertical motion.(Equal and opposite voltages can-cel each other.) For stereo appli-cations it is also possible electricallyto mix a portion of the low frequen-cies in both channels so that thevertical rumble component is can-celled out. It can be done withoutcompromising the stereo effect.Many cartridge makers are usingmechanical vertical -suppression de-vices, usually in the form of abumper or buffer wedged betweenthe stylus and cartridge body. Someare using the electronic mixingmethod which may consist of abridging resistor from one elementto the other.
3 -Pin or 4 -PinSome question will no doubt be
raised about the use of 3 or 4 -terminal cartridges. For most appli-cations the 3 -terminal units arequite satisfactory, and if all other
conditions are the same, no dif-ference in performance will benoticed. An advantage offered bythe 4 -terminal cartridge is the avail-ability of separate ground connec-tors. Benefits from this feature canbe realized if a ground loop is en-countered or if for some other rea-son unstable problems should arisefrom a common ground connectionat the cartridge end.
If it should become necessary toalter the phasing characteristics ofthe stereo cartridge, in the field, itcould be readily accomplished withthe 4 terminal units. The systemshave been standardized to the point,where it should not be necessary toresort to such phasing gimmicks.The experimenter may for somereason wish to connect both ele-ments in series; this configuration ispossible with either the 3 or 4 ter-minal cartridge. In some cases, inorder to minimize hum and satisfywiring conditions the two groundterminals in the 4 -terminal car-tridge may have to be tied together.However, the added flexibility of thefourth terminal is desirable, but notnecessary, for some of the reasonsadvanced. A certain amount of pre-caution should be exercised wheninterconnecting two ac -dc type am-plifiers, or other equipment, espe-cially if the chassis are connectedto one side of the power line. If thelow side of the plugs or jacks areconnected to the chassis there is adanger of placing 117 volts acrossthe two ground terminals on the4 -pin cartridge which may be spacedless than 1/16" apart, as shown inFig. 4. Normally these jacks are notat chassis ground. Concern here isnot so much for equipment protec-tion as it is for protection of theequipment user. The 3 -terminal
Fig. 3-Relative output voltages obtained from various stylus motions. In -phase me-chanical forces result in out -of -phase electrical signals. Conversely, out -of -phase me-chanical forces cause in -phase signal. Because low frequencies are essentially in -phasesignals, they will be found mostly in the horizonal components of the stereo disc.
ELECTRICAL PHASEOUT IN
-+ +
tIN OUT
MECHANICAL PHASE
}SIGNALVOLTAGE
POLARITY
STYLUSMOT/ON
cartridge in this situation would bea safer bet, because the house fuseor wires going to the cartridgewould let go instead of leaving apotential shock hazard. Fortunatelymost if not all high fidelity equip-ment is power transformer equippedand line voltage leakage to groundis within safe limits.
Impedance MatchingIn general, impedance matching
requirements are the same. How-ever, in all cases the manufacturer'sspecifications should be consulted.Certain normal load conditionswhich may be satisfactory in manyinstances can be noticeably im-proved by the addition or change ofonly one resistor. The velocity sen-sitive cartridges which include the
Fig. 4-Possible shock hazard may be set up,with some AC DC equipment and cartridges.
magnetic, variable reluctance, mov-ing coil, and moving iron require anequalized preamplifier for eachchannel. The conventional types aresatisfactory in most cases. The ce-ramics and other high level outputcartridges generally can work di-rectly into the amplifier. The outputversus frequency response curve forthese cartridges are equal to thecompliment of the RIAA recordingcurve, and therefore the amplifiershould have a flat frequency re-sponse.
When the normal high impedanceinput in amplifiers which are in theorder of 500,000 ohms are used forstereo, they will attenuate some ofthe low frequencies. This conditionis easily remedied by following theinstructions for each cartridge,which usually specifies an increasein the input resistance. In somecases up to 8 megohms are recom-mended.
Certain desirable design charac-teristics are responsible for smallersignal output from the stereo car-tridge. There is usually more thanenough reserve gain in the pream-plifier and amplifier to provide asatisfactory output level.
ELECTRONIC TECHNICIAN Stereo, 1959 55
Needles For StereoVertical Sensitivity Of Cartridge Requires Additional
Precautions To Avoid Distortion And Tracking Problems.
CHARACTERISTICS
ElectricalDistortion
IMHarmonic
Noise
MechanicalExcessive WearTracking
InstallationAlignmentPressureSizeMaterialQuality
In spite of certain claims of com-patibility in various respects for thenew stereo disc systems, a closerlook reveals that, while the same sty-lus and pickup will play both themonophonic and the new stereo discsit is advisable to use the right stylusfor each. Here's a quick rundown onthe way the new stereo records af-fect the needle problem.
Both systems use the RIAA curve,therefore the problem frequencies(preemphasized highs) are the sameas regards to having the needle fol-low the groove. This is shown inFig. 1. The extremely vigorousmovement represented at 10,000
Fig 1-Relative stylus motion at differentfrequencies at maximum recording level forfour frequencies, using the RIAA curve.
cycles is offset for much of the timeby the relatively low level of thesehigh frequencies. But, certain soundswith high impact components, suchas cymbal clashes, triangle, drum-mer's traps, a plucked steel guitar,xylophone or marimba played withhard -surface mallets, can producean extreme demand on needle move-ment. These place the greatest strain
CUTTINGSTYLUS
GROOVEWIDTHEQUALSSTYLUSWIDTH
III IS//II\
,\Ty -CROSS-SECTION
AT RIGHT ANGLETO NEEDLE TRAVEL
' LEWD, TO EDGED AMMO
RECORD GROOVE
TOP VIEW
GROOVEWIDTH
LESS THANSTYLUSWIDTH
Fig. 2-Sidewise motion of the cutter makesthe groove narrower and subsequently forcesa round stylus to rise. A 1,000 cycle sinewave even though impressed laterally, causesthe playback needle to rise and fall 2,000times.
on stylus and disc in both systems,often amounting to 2,000 times thenormal force required to move thestylus.
There has been much talk aboutpinch effect. Pinch in a monophonicrecord is actually a narrowing of thegroove width, caused by sidewisemovements of the cutting stylus,during the recording process. Whenthe relative motion between the discand cutter is straight ahead, thewidth of the groove is maximum.Thus when recording a sinusoidalsignal the groove width is maximumonly at the peaks, also when there isno modulation, as shown in Fig. 2.Because the playback needle isround, (same radius in all direc-
LARGE STYLUS
DiPSIRTOODRUTCEEDS
MOTION
NEEDLEPATHS,
LARGE/
VERTICALRECORDEDCOMPONENT
SMALLERSTYLUS
REDUCESDISTORTION
CROSS-SECTIONLLEL TO NEEDLE TRAVEL
Fig. 3-The path of the larger stylus differsfrom the actual vertical component causingdistortion. The smaller stylus minimizes thisdistortion. Compare dotted and solid lines.
tions) it is forced to travel up anddown twice for each sine wave, or2,000 times for a 1,000 cycle signal.Provided vertical motion of the sty-lus produced no output from thepickup, this was relatively unim-portant. But stereo records usevertical motion as well as lateral(even though it may be resolved as45/45), therefore pinch effect canno longer be inconsequential. Pincheffect in stereo discs has three kindsof pickup between vertical and
(Continued on page 97)
Fig. 4A-Largei stylus with normal pressureis liable to bounce. 113) Increased pressureimproves tracking, but deforms the groove.
NORMALPRESSURE
GREATERPRESSURE
DISTORTEDSHAPE
/' OF GROOVE '4
ORIGINAL SHAPEOF GROOVE
56 ELECTRONIC TECHNICIAN Stereo, 1959
Best for
Conversion
or Replacement
COLUMBIA CD...by design the
most linear Stereo Cartridge
+5
0)
-5
RESPONSE OF COLUMBIA CD CARTRIDGE
mimmeolo.
20 100 1000FREQUENCY IN CYCLES PER SECOND
+5
0
-5
10000 20000
anus
COLUMBIA CD LinkageIn Columbia Constant Displacementcartridges, motion of the stylus is trans-mitted directly to the two wafers thatgenerate the output voltages. This isaccomplished by a simple lever, frictionless and featherweight.The precise mechanical design assures that, regardless of fre-quency, the output voltage is essentially constant for a givendisplacement of the stylus.
Ask to hear the CD. Discover for yourself that ColumbiaConstant Displacement cartridges are designed to reproduce allthe exciting breadth, depth and realism of stereo records. Re-member, the Columbia CD was designed by CBS-Hytron'ssister division Columbia Records drawing on its over 60 yearsof recording experience. Get the best. Insist on ColumbiaConstant Displacement cartridges.
CERAMICS
Now is the time to profit fromstereo. And for stereo conversionor replacement, Columbia CDcartridges are designed to be yourbest choice. Note the advantagesof their constant displacementdesign. Check specifications.
Ask your CBS-Hytron distribu-tor or write us for helpful freebulletins: An Introduction toStereophonic Sound, E-305; Hintson Using the Columbia CD StereoCartridge, E-306; InstructionSheet for the CD, E-289. Orderthese bulletins and your ColumbiaCD cartridges . . . today.
SPECIFICATIONSDiamond stylus 0 0008 inch radius
Recommended needle force 5 to 7 grams
High compliance.superior tracking and reproduction
Open -circuit voltage 0.5 volts
Extended stereo range, ±2.5 db....20 to 16,000 cps
Channel separation in excess of 20 db
Complete compatibility stereo and monaural
4 speeds 331/4, 45, 78 and 16%
C B S-HYTR 0 N, Danvers, Massachusetts
A Division of Columbia Broadcasting System, Inc.
Circle 57-01 on inquiry form page 73ELECTRONIC TECHNICIAN Stereo, 1959 57
high fidelity
FMreception
demands a fine antenna. . . and the audiophile's best bet for clear, sparkling FM
sound is an AMPHENOL broadband FM antenna. Available
in two popular models, AMPHENOL FM antennas have been
carefully engineered for specific reception problems. The
114-008 "Inline-type" folded dipole and reflector offersthe unidirectional directivity pattern, high gain and me-chanical rigidity that have made AMPHENOL'S tv Inline
antenna famous. The 114-010 "Turnstile" double foldeddipole is intended for use in urban areas where thereare many FM stations. Its circular directivity patternassures efficient pick-up of such stations.
* Do it yourselfCOMPLETE KITS $16.25 each, list
AivipMENoLAMPHENOL ELECTRONICS CORPORATION chicago50,il/inois
58
Stereo Conversions
(Continued from page 52)If a problem of excessive vertical
rumble from the record changershould present itself on stereo pro-grams, it is possible to make thestereo pickup less sensitive to verti-cal displacement by placing a re-sistor across the two hot leads onthe cartridge. It will also be neces-sary to connect both ground leadstogether on a 4 -pin cartridge. Thestereo effect will not be materiallycompromised by this gimmick. Thevalue of this resistor can best bedetermined by experiment; 1/2 to2 megohms should do the trick inmost instances.
Extra shielding and precautionsare necessary for hum -free listen-ing. It may be necessary to try sev-eral different methods to obtainbest results. Because of the lowsignal levels at the cartridge outputand the necessary high amplificationfactors, any noise or hum that getsinto the front end of the amplifieris going to be heard. Because ofthis and the increased number ofinterconnections from one unit toanother, an undesirable groundloop may develop. In stubborn sit-uations, it may be necessary to trya different cartridge. In most situa-tions observing the rules laveddown by the manufacturer forgrounding and connecting his pieceof equipment will do.
The muting switch on a recordchanger presents a problem and thetechnician's mechanical ingenuitywill come to light. The switch nor-mally grounds the hot terminal dur-inc the change cycle and sometimeswhen the tone arm is in its restingPosition. The problem stems fromthe fact that a duplicate set of con-tacts is needed for stereo. In somecases it may be possible to impro-vise another effective electrical poleby substituting a conducting ratherthan an insulating switch armature.Other switch modifications will sug-gest themselves upon inspection. Inall probability, later versions of rec-ord changers will eliminate thisproblem by incorporating a dualswitch.
Stereo is here ... and conversionsto stereo can be difficut for the in-experienced. In the light of presentdevelopments it is worthwhile toinstall a stereo cartridge as soon aspossible. For best results, the con-version should be performed bypeople with the skills of a qualifiedtechnician. .
4Circle 58-01 on inquiry form p. 73
ELECTRONIC TECHNICIAN Stereo, 1959
firsawmommuli
Famous V -MRecord Changers
Have GreaterConsumer
AcceptanceTHAN ANY
OTHER MAKE!
V -M HAS MANUFACTURED MORE STEREO CHANGERS THAN ANY OTHER MANUFACTURER!
The All -New V -M 'STERE-0-MATIC" 4 -SPEED RECORD CHANGER
This is the one automatic record changer that matches all otherchangers feature for feature and then some! V -M's `Stere-0-Matic' Model 1201 comes wired for stereo with stereo cartridgeinstalled! Complete with dual output jacks and stereo/mon-aural switch $50.00 List*
SEE AND TEST THIS HIGHEST QUALITY STEREO RECORD CHANGER WITH TRUE, TRANSCRIPTION -TURNTABLE PERFORMANCE.
RUMBLE: -48 db for 120 cycle rumble when tested onXLP414 test record (recorded velocity approximately 3.4cm/sec. at 1,000 cycles.)WOW AND FLUTTER: Vs RMSTURNTABLE: Balanced to assure constant speed. Bearingmaterials and finishes controlled for minimum noise andfriction. Spindle bearing area centerless ground to reduce'frictionar drag.MOTOR SPEED: Constant, positive for permanent truepitch.
TONE ARM: Resonance -free. Easily adjustable for anycartridge weight. Compensated to eliminate variationfrom bottom -to -top of record stack. Jewel -type anti -frictionbearings eliminate vertical friction. Stereo cartridge in-stalled. Will accept all popular stereo or monaural car-tridges without alteration.TRACKING ANGLE: Variation reduced to a maximumof 2°.
AUTOMATIC SHUT-OFF: Unit shuts off automaticallyafter last record plays.
RECORD INTERMIX: Will intermix changing of 10"and 12"records of the same speed. V -M 45 spindle fits easily overTri-O-Matic spindle for 45 rpm records.Model 1202 has 4 -pole motor and plug-in head for GEand other magnetic cartridges. All stereo leads, jacks andswitch included $50.00 List*
Both available with matching base -pan as Models 1226 and 1228.V-M-PIONEER IN STEREO-YOUR ASSURANCE OF THE HIGHEST QUALITY!
*Slightly higher in the West
theoice of Music®V -M CORPORATION BENTON HARBOR, MICHIGAN
World Famous for the Finest in Tope Recorders, Phonograph; and Record Changers
Circle 59-01 on inquiry form page 73ELECTRONIC TECHNICIAN Stereo, 1959 59
r --FM RECEIVER
(A+B) + (A -B) (A+B) + (A-8)
FRONTEND
L
IFAMPLI-FIERS
7-2nd
DETECTOR 00-
r
DE -EMPHASISNETWORK
- -1
A+B
4 FILTER
1
( A +8) + ( A-8) .2y
AUDIOAMPLIFIER
A -B A+B
DEMOD- PHASEULATOR SPLITTER
A-8
MULTIPLEX ADAPTER
AUDIO
AMPLIFIER
(A+8) - (A-8) 2 E\
Fig. 1-Conventional FM receiver picks up the entire multiplexed pro-gram, but only the monophonic information (A+13) can be heard. The
IA -B) signal can be picked off by a multiplex odaptor and fed into bothspeaker systems to establ sh the left and right sense.
AAultipleH Stereocasting
Multiplex transmission very sim-ply stated is the transmission ofmore than one program on the samecarrier. This differs from the typeof transmission found in TV. True,two programs (sound and video)are sent over one TV channel, butseparate carriers are used for each,and it is possible to tune in one orthe other. In the case of multiplex-ing, a portion of its carrier is leftclear of the main program to Accom-modate a second channel withoutincreasing bandwidth. To help iden-
tify the various portions, they aretermed main carrier and subcarrier.Unlike the TV signal it is not pos-sible to tune in the subcarrier with-out receiving the main carrier.However, it is possible to filter outthe information on the main carrierleaving only the intelligence con-tained in the subcarrier. Just as itis possible to create a se -calledsecond channel with its related sub-carrier, it is possible to subdividethe main carrier into many sub -carriers, and transmit many differ-ent programs at the same time.Some FM staions which are alreadyusing multiplex to broadcast a pro -
Fig. 2-Sum and Difference technique supplies all the information needed for monophoniclistening to the main program. The sum signals modulate the main carrier and the differencesignals are impressed on the subcarrier.
ADDITIVEMIXER
A+B
CONTAINS ALL
INFORMATION NEEDED FORMONOPHONIC RECEPTION
A+B
DIFFERENCEMIXER
A -B
AFAMPLIFIER
AFAMP.
SUB -CARRIER
MOD.
A -B
SUB -CARRIER
MIXER
"STEREO"COMPONENT
ON
MULTIPLEX
(A+B) + (A -B)
(A +8)
(A -B)
FMMOD40_
TRANSMITTERCARRIER
GENERATOR
gram into the home, free to thelistener, and beam a backgroundmusic program into commercial es-tablishments for pay, are consider-ing the use of a second subcarrierfor stereocasting. This would prob-ably divide the station's signal sothat the major portion of the car-rier would consist of the mainbroadcast program; the next ad-jacent subcarrier would carry theinformation needed for stereo; andthe end subcarrier would continueto provide a source of income fromcommerical listeners.
How to maintain compatibility toenable the regular FM listener toget his full quality program withoutinterference from the other portionsof the multiplexed signal, and howto avoid other problems of poorsignal-to-noise ratio, crosstalk, anddistortion for the listener of thesubcarrier portions, presented somemean problems to the broadcasters.That they have succeeded in devel-oping a workable system is verymuch to their credit. In the AM -FMtechnique of broadcasting stereo, itis necessary for each of the twochannels to contain all the programinformation. Therefore the micro-phone for each channel must, in thisapplication, be placed fairly closetogether and in the center. Thisclose spacing was also used in someearly multiplexing efforts; it goes
(Continued on page 62)
60 ELECTRONIC TECHNICIAN Stereo, 1959
This is part of one of the four testing bays at University where each speaker that leavesthe factory goes through a series of exacting tests. Here we see a Model 315-C 15" JwayDiffaxial being tested for frequency response. As the speaker is "swept" through the entirefrequency range, its audio output is fed via a sound box, microphone and amplifier to theoscilloscope where marker lines check that it conforms to laboratory standards within 1 db.
UNIVERSITYAFLSPEAKERS
ARE
ST EREO -MATCHED
within 1 db because.
Only properly matched speakers... matched toproduce the same frequency response, tonal balanceand sound output level throughout their specifiedranges ... can achieve true high fidelity stereo. "Mis-match," in the all-important directional mid andtreble ranges, can cause an unwanted shift ofemphasis from one speaker to another. "Mismatch"in timbre or tonal balance becomes especially dis-turbing where the voice or instrument actuallymoves from one channel to another ... as in opera,marching bands, or special effects. Also, the har-monic relationship between fundamentals and over-tones must be reproduced identically so that bothchannels match in tone and timbre.
That's why engineers advise you to use match-ing speakers or speaker systems for stereo-preferablythe same models from one manufacturer. But if pro-duction standards change, if tight quality checksaren't maintained, even speakers in the same produc-tion run, with identical model numbers, may be mis-matched. No problem with monaural. Bad for stereo.But a risk you need never take with University!
Every University speaker or system matches thefrequency response and sound output level ofany other of the same model within I db.
If you now have a University speaker, you areindeed fortunate, because you can go to any Uni-versity dealer anywhere and get a speaker thatmatches perfectly for stereo.
If you are planning stereo from scratch, orstarting with monaural for later conversion, Univer-sity's famous P-SE (progressive speaker expansion)plan gives you complete loudspeaker planning flexi-bility. Start with any two wide -range speakers to fityour budget ... simply add complementary speakerswhenever you wish to achieve your ultimate aspira-tions. Whatever your choice, you can be assured ofperfect stereo performance.
...THAT'S WHY UNIVERSITYIS THE SAFEST, MOST LOGICAL
CHOICE FOR STEREO!
For FREE LITERATURE on all University speakers, speaker systems, enclosures and, kits-plus the fullPSE story-write Desk Z-6, University Loudspeakers, Inc., 80 South Kensico Avenue, White Plains, N. Y.
LISTEN saunas 6e0it
PERFECT
FOR MONAURAL...PERFECTLY MATCHED
FOR STEREO...
there's a Universityspeaker or system tomeet your space orbudget requirements.)
ELECTRONIC TECHNICIAN Stereo, 1959Circle 61-01 on inquiry form page 73
61
or'd something wonderful happens!You're there . . . reliving the original performance,
hearing the songs you love with a newbrilliant clarity . . . hearing the depth of life
in each musical passage. GrommesStereo is stereophonic reproduction at
it's finest . . . superb fidelitywith a new realistic depth ...bringing you truly, music
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You he the judge . .. Your Grommes High Fidelity Dealerwill be happy to demonstrate this exciting new line ofGrommes Stereo Amplifiers.
Send me full detailson the new GrommesStereo Line
Grommes_ Division of Precision Electronics Inc.Dept. T-9, 9101 King Street, Franklin Park, Illinois
Name
Street
City Zone State
Circle 62-01 on inquiry form p. 73
Multiplexing
(Continued from page 60)
back to the pre -stereo days whenbinaural was contemplated. The bi-naural concept was to feed each earthe same type of information aswould be heard from some theoreti-cal ideal listening point. This wasaccomplished by placing the micro-phones apart as little as six inches,which is supposed to be the distancefrom ear -to -ear on an average per-son, and then feeding this informa-tion through two separate ampli-fiers, and finally to the listener'sears via a set of headphones.
The concept of present day stereoprovides considerably more freedomand a more realistic listening con-dition in the home. No longer is it
CARR ER
ill \0 15 KC
MAIN CARRIER SUB -CARRIER
I \I ...\.MAIN CARRIER
15KC 50KC
SUB- SUB -CARRIER CARRIER
I Anno I5KC 40KC 60KC
Fig. 3-By restricting the deviation of themain program, it is possible to leave enoughroom for one or more subcarriers to conveyadditional programs. Relative deviation anddistribution of energy are shown.
necessary to wear a pair of ear-phones. When the listener is sittingoff to one side of the room, it isas though he were off to one side ina concert hall; by the same tokenif he were seated in the center ofthe room, the feeling would be asthough the musicians were spreadout in front of him. In other words,stereo offers certain desirable spa-tial characteristics that binauraldoesn't.
Because it is not necessary for thestereo subcarrier to stand on itsown feet so to speak, it is possibleto take advantage of another micro-phoning technique which improvesthe stereophonic effect and stillleaves all the necessary information
62ELECTRONIC TECHNICIAN Stereo, 1959
in the main carrier for monophoniclistening. Thus a listener who doesriot have a multiplex setup will stillbe able to get his FM station with-out any noticeable loss in quality.
The manner in which, this is ac-complished is quite interesting. Themicrophones can now be placed fur-ther apart and at more advanta-geous positions. Microphoning tech-niques are a study unto themselves.There are an infinite number ofpoints where they can be located,and an equal number of directionsthey can be facing. Directional char-acteristics of each microphone usedalso plays a vital roll in the stereoproduction. However, the importantthing at the moment is what hap-pens to the signals after they leavethe microphones. Fig. 2 shows howthe two signals from each micro-phone (A and B, or L and R for leftand right) are added and fed intothe main channel. This is essentiallywhat is done in monophonic prac-tice. Since all the information ispresent in this A+B signal, it is
MICROPHONES AMPLIFIERS HEADPHONES
Fig. 4-The binaural concept projects a the-oretical ideal listening point to the listener.
the one that is used to modulatethe main carrier. For the otherchannel the two microphone outputsare combined to form a differencesignal. This is not difficult: it isonly necessary to pass one of thesignals through a phase inverter.The A -B component thus developedis then used to frequency modulatethe subcarrier, which in turn isused to frequency modulate themain carrier.
The signal A+B is fine for mono-phonic listening, even A -B mayconvey enough information to theinexperienced ear, but A+B andA-B as such do not as yet haveany significance so far as stereo isconcerned. Something else musthappen before the right and leftsense is restored. This is readily ac-complished at the receiver end asshown in Fig. 1. By adding a portionof each signal to each stereo chan-nel amplifier, but once again chang-ing the phase of one signal in onechannel, the righthand speaker will
(Continued on page 95)
We are sucplyingstandare. Garrard tthangersand turntables to stmeo cart-ridge manufacturem for testpurposes. Knowing of yourinterest in the new --__t devel-apments-we reprod xe, withpermissier_, some of the com-ments wa have receive.
Stare° performance is inher-ently extra -sensitive to suchsymptoms as rumble andwow. This makes the selec-:ion of record play_n_g equip-ment ever_ more critical thanIn the nost.
We lavetested
rota:ing coilstereo cartridge
4changeraWnidth firstrcurthat itis perfectlysuitabla forplaying stereoorwith tILSchanger.
Toebee°3rentati'rl Proved
stern'e forrdo-up-ch
we wouldha, andhesi ta-iz
recommena..-ilcartridge 6 our
e no
changer.
please
mtifhs°aidt :Garrardekno
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For all records-stereo and mongural
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Circle 63-01 on inquiry form p 73ELECTRONIC TECHNICIAN Stereo, 1959 63
Stereo Tape and Tape Recorders
New Materials, Techniques, And Developments Assure
The Tape Recorder A Prominent Position In The Hi Fi System.
Tape was really the first mediumto find fairly extensive acceptanceas a source for stereo programs. Thiswas a natural development. Record-ings were first placed on tape beforetransferring to disc for some time.The record companies found it use-ful to simultaneously record severaldifferent tracks from individualmicrophones placed in different po-sitions and then blend them togetherlater to obtain an optimized effectfor transfer to the disc. This means
r11 I. RA
TRACK 2 j ; HA,? I t__ ; t11
STAGGERED HEADS STACKED HEADSALLOW MORE ROOM PLAY TRACKS SIDE -Br -SW
FOR GENEROUS SZE HEADS AND ARE COMPACT
Fig. 1-Staggered and stacked heads as usedin tape recorders. Some machines have both.
the record companies' master tapes,by accident or design, are already ina stereo form. As progress in stereodevelopment went forward, it be-came evident that the new mediumpresented a potential for later re-lease of the same monophonic pro-grams in stereo.
The development of half-tracktape (two tracks on one tape) as asource of extra -long-playing pro-gram material opened the way forusing both tracks in the same direc-tion and putting two -channel stereoon them./ While there is no doubt that tapes,made and transcribed on really topquality machines, can yield betterquality than discs, the scaled downprerecorded tapes played on lowpriced tape players or recorders,have had a tough time competingwith discs for quality in similarlypriced systems, although they have
always had the advantage of longeruninterrupted playing time. This re-duction in quality was forced by thequestion of economics in both tapeand recorder cost.
Record masters have mostly usedat least 15 inches -per -second (ips),and often wider than the standard1/4" tape, to get the best possible dy-namic range and quality. Prere-corded tapes have been transferred,by high-speed multiple -copying ma-chines onto 1/4" tapes with two 71/2ips tracks. Higher quality results at71/2 ips, but the appeal of the longerplaying time at lower cost will un-doubtedly encourage the trend to-ward 33/4 ips. Most machines willrun at either speeds.
This "stretching" of tape, gettingonto narrower tracks, and running atslower speed, has not resulted en-tirely in proportionate loss of qual-ity, because the head and tape man-ufacturers have been busy too. Theyhave come up with products thatutilize the lower speeds and nar-rower widths much more effectively.It is reported that a half-track 71/2ips tape, recorded and played withtoday's best heads, is at least as goodas yesterday's full -track 15 ips tapes.
Head ArrangementsStereo presented a problem of how
to arrange the two heads. In theearly days materials and productiontechniques necessitated a fairlybulky head to get the best qualitywhich led to the use of staggeredheads. Because of tape stretch andother mechanical tolerances, it wasobviously more logical to have bothtracks run side -by -side, in time aswell as place to avoid phasing prob-lems. So another group preferredstacked heads. Both types are shownin Fig. 1. At present the stackedgroup seems to have had the bestforesight. Techniques for makingheads has improved to the pointwhere just as good quality can be
obtained from the stacked arrange-ment. Some recorders have pro-vision for playing both.
To keep pace with the competitionfrom the new stereo discs, to makethe use of tape more economical, andto further the art, the tape engineershave been working on quarter tracktape for stereo. Before, there weretwo tracks on a 1/4" tape, whichcould be used separately for mono-phonic channels or together forstereo. The four channel tape shownin Fig. 2 will accommodate two sep-arate two -channel stereo programs
FULL TRACK HALF TRACK QUARTER TRACK
ONE WAYTWO WAYS FOR MONO
OR:
ONE RAT fUR STEREO
FOUR WAYS FOR MONOTWO WAYS FOR sower)
Fig. 2-Progressive development from theoriginal full -track tape to half-track, and nowto the new quarter -track, which can beplayed stereophonically in both directions.
or four single channel recordings.All other things being equal, thiswould again result in a deteriorationof dynamic range. But again produ-tion methods, both on tape andheads, continue to develop and itmay result in no deterioration incomparison with former one-waystereo tapes.
A recently introduced tape cart-ridge (all tape wound inside thecartridge) using a four track, 1/4",600', tape at a speed of 33/4 ips, re-duces the amount of manipulationrequired to set up, and eliminatesconventional reels and the need forthreading. Tracks 1 and 3 are usedfor stereo play in one direction, andtracks 2 and 4 in the other. Auto-matic and semi -automatic machinesto handle these tape magazines orcartridges have been demonstrated.At this time only a limited number
64 ELECTRONIC TECHNICIAN Stereo, 1959
of cartridge machines are on themarket. Sound quality is said to beas good as the two -channel tapes.
One of the big attractions to taperecorders, is the ability to make re-cordings. Most of the earlier stereosystems could be converted to, orwere provided with facilities forplayback but not recording stereo.A number of the newer releaseshave provision for recording stereo.Home stereo recording requiresmore know how. Most recordingswill probably be made in the livingroom. The average living room re-quires a very different techniquefrom that used in stereo recordingstudios.
Two directional type microphonesare desirable. A pair of qualitycardioids can give very good results.The microphones could then be di-rected toward different parts of theroom, group, piano, etc. Because thedirectional effect in sound is due toeither a difference in sound intensityor a phase difference, and becausein the average size living room thereis only moderate difference in soundintensity when a person is speakingfrom a few feet away or from the op-posite side of the room, it is essentialthat the microphones have good di-rectional characteristics for goodstereo effect.
In an auditorium or other fairlylarge area, there may still be someadvantage to using directional micro-phones, but good results can be ob-tained with the ordinary, mostlyomnidirectional, types usually fur-nished with the recorder.
Techniques will vary with eachset-up. If possible it is a good idea toconduct a few trial runs before at-tempting to record a formal pro-gram. Theoretically, the micro-phones should be placed in the sameposition and same spacing as the earsof an ideal listener; but because ofthe absence of certain psychologicaleffects, including the inability to seethe performers or their instrumentswhen the recording is played back.wider spacing of the microphoneswill help create the stereo effect. Adistance of about 3 feet may be agood start. When recording pianomusic, it may be possible to place amike on each side. Thus one willpick up the bass while the other willreceive the sound from the treblestrings.
If the mikes are placed too farapart, "ping pong" and other unde-sirable effects may be encountered.As a general rule, directional micro-phones may be placed closer to-gether while omnidirectional typeswill create a better stereo effect ifplaced closer to the dominant endsof the sound source.
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Circle 65-01 on inquiry fo,m p. 73ELECTRONIC TECHNICIAN Stereo, 1959 65
STEREO EFFEC1.-DUE TeBEAMINdOFHIGH FREQUENCIES ..-
AREAOF
STEREO
/
Fig. 1-Two speakers in one enclosure,angled away from each other can createpleasing stereo effects even when the listeneris not seated in the true stereo area.
Speaker
AREA OF
MID,RANGE FREQUENCIES CONTRIBUTEMOST TO THE STEREO EFFECT IN THIS AREA
Fig. 2-Separate speaker sys-tems are more desirable particu-larly for larger listening areas.
WINDOWS
LIVINGROOM
[2nd CHANNEL
ARCH WAY
DINING ROOM
( O
0ONE CHANNEL
TWEETER -Ab.,MID -RANGE
MAIN WOOFER-w.
I I
I KITCHEN
Fig. 3-Multiple speaker system arrangedso that the high frequencies are projectedalong the sides of the wall while themidrange is aimed at a central rearwardportion of the room. Because of spacelimitations only one woofer is used atpostion A to furnish the necessary bass.
Arrangements For Stereo
A good general rule to use as astarting point is that the smallerliving room, up to 12 feet by 14 feet,can be served by two enclosures ora single enclosure type of stereo-phonic speaker system, with thespeakers sufficiently separated andpointing outwards as shown in Fig.1. For larger rooms it is better toarrange two separate enclosures andtheir speakers along the shorter wallof the room as shown in Fig. 2.While corner placement is desirable,it isn't absolutely necessary. Theshaded portion indicates the socalled true stereo listening area. Thedirection or angle of the speakers isalso important. Generally, the highfrequencies should be directed downthe sides of the room, and perhapsa bit toward its adjacent side wall.This helps to get the higher fre-quencies into portions of the roomwhere the true stereo effect is notrealized, but will nevertheless helpto create a pleasing stereo illusion.Angling the woofers so that it coversthe central listening area offers the
same advantages, and for the samereasons, found in monophonic hi-fipractice.
This is an easy basic rule, but inactual practice modifying andadapting to suit the circumstancesof individual living rooms will berequired. Room shape, furnishings,and position of doors, windows, etc.,will often make it impossible toadopt the ideal speaker placementand listening positions.
To provide the foundation for ap-proaching any particular installationso as to make the best of the cir-cumstances, it is necessary to knowjust what it is that stereophonicsound has to do. Many conflictingstatements have been made by dif-ferent authorities on just how ster-eophonic effects are really achieved,so differences of opinion are inevi-table.
Practical experimentation hasshown that the bass frequencies(below about 250 cycles) do not inthemselves contribute anything tothe stereophonic effect. However,sounds below 250 cycles do have asense of direction, but it is due totheir harmonics and other compo-nents which are above this range.
These low frequencies are the onesthat require the larger speakersand enclosures. However, in smallrooms, speakers using the acousticsuspension principle have the ad-vantage of smaller enclosures andgood bass response. If there is onlyone good corner location, or a po-sition where a bass reflex or othertype of enclosure, which can do agood job of reproducing the lowfrequencies, it will be quite in orderto use a smaller speaker for thesecond side without attempting toget too much bass out of it. Bassfrequencies referred to are thosebelow 250 cycles. Provided adequatebass is fed into the room from atleast one of the speakers, the ster-eophonic illusion or effect will besatisfactory.
If this method is used, it is well toemploy a multi -speaker system forthe side that delivers the bass,preferably with a turnover in theregion of 250 cycles, and certainlynot higher than 350. This enablesthe woofer to concentrate on thelow notes and permits the midrangeand tweeter, speakers to performthe function of delivering the stereoeffects with maximum efficiency.
66 ELECTRONIC TECHNICIAN Stereo, 1959
This range from 250 to 1,500cycles may be termed the range oftrue stereo. It is this range of fre-quencies that conforms best to thetheory of stereo. But this does notmean that it is only necessary toconcentrate on getting only 250 to1,500 cycles. Frequencies above andbelow this range are also importantfor getting good stereophonic repro-duction, but for different reasons.
The so-called true stereo effect ismost critical of listening position.If the midrange frequencies only
CHANNELYI
PREANP
STEREOINPUTS
(TAPE ,11A010
or MC)
CHANNEL
2PAEAMP
ELECTRONIC
CROSSOVER
25o,
ABOVE50
ELECTRONIC
CROSSOVER
250,,
BELOW250
E 0250
CHANNEL
tAI
ARP
CHANNEL
2
AMP
WOOFER
TO CHANNEL
so I
MID -RANGE
TWEETER
TO CHANNEL
'2MID-RANCE
TWEETER
TO SINGLE
WOOFER
Fig. 4-Electronic crossover removes thebass component from each channel andfeeds it into another amplifier andspeaker system to form a third channel.
were present, the stereo effect wouldonly be achieved in the shaded areasin Figs. 1 & 2. But, still other effectscontribute to the desired stereo il-lusion, much more than many peo-ple seem to realize. The distributionof the high frequencies, those above1,500 cycles, can help considerably.
This can be demonstrated by thearrangement shown in Fig. 1. Thestereo effect in this case is obtainedby beaming the high frequenciesfrom each channel directly at theadjacent side wall. Thus one groupof high frequencies is comingtoward the listener seated off to oneside, while the other group of highfrequencies is directed away. Thisgive an overall effect, at positionsoff -center, very similar to sitting atone side of a concert hall. By thismeans a very real sense of perspec-tive is retained even though the truestereo effect which is dependentprincipally upon the mid -range fre-quencies is lost when not in thecenter of the room. The general ef-fect of a speaker system of thistype in a smaller room, with areasonable degree of furnishing, canbe quite pleasing.
Typical ProblemsIn the first place it is necesary to
know how much one is prepared tospend. Then it can be decidedwhether to get single extended -range speakers or multiple -unittypes. With a good extended rangetype speaker, the stereo effect basedon the mid -range frequencies must
be depended upon, because extendedrange units tend to scatter the highfrequencies in a rather indetermin-ate fashion compared with mosttweeters. On the other hand themultiple speaker systems can beused to make the best of some awk-ward listening room conditions or toextend the useful listening area.
To better understand the applica-tions of these principles, considersome of the more difficult but notunusual situations. This fairly largeliving room has a relatively largeopening in the shorter wall leadinginto the dining room, as shown inFig. 3 A corner type enclosure witha multiple speaker system could beplaced in the position marked A.Then the most desirable position forthe second speaker would be some-where in the vicinity marked B. Butthere is very little room to put aspeaker here; certainly not a largecorner or wall type enclosure. Thecorner type would project into theopening, while the wall type, with itsback against the wall, would projectthe sound in the wrong direction.This location calls for a muchsmaller speaker -enclosure arrange -
CHANNELYI
AMP
CHANNEL
2AMP
ELECTRONIC
CROSSOVER
250,
ELECTRONIC
CROSSOVER
250, I
TO CHANNEL*I
MID -RANGE
V TWEETER
TO CHANNEL*2
MID -RANGE
& TWEETER
TO SINGLE WOOFER
Fig. 5-If the crossover network is insertedbetween the amplifiers and speakers, it is
possible to avoid the use of a third am-plifier, and still have the third channel.
ment. It now becomes a case for thespeaker positioned at A to furnishall the bass. It is possible but notnecessary to elaborate on this sys-tem by combining the bass fromboth channels using a couple ofelectronic cross-overs and feedingit to the woofer. Thus relying en-tirely on the separation of those fre-quencies above 250 cycles for eachchannel, to get the stereophonic ef-fect, as shown in Fig. 4. This hookupshows three amplifiers. It can bedone with two amplifiers by insert-ing the crossover network betweenthe amplifier for each channel andthe speakers as shown in Fig. 5.The midrange speakers should bedirected so that the true stereo ef-fect, is achieved in the central partof the far end of the room. The highfrequencies from the tweeters couldbe directed to cover the areas notproperly covered by true stereo.
Therefore, the midrange speakersshould be aimed toward the middleof the room, a little more towardthe rear, while the tweeters shouldbe aimed down the sides of theroom. In some speaker arrange-ments it is posible to adjust theangle of the speaker at any time tosuit the program material and seat-ing arrangement. In some installa-tions where the speaker enclosureitself is sitting inside another pieceof furniture, it is possible to anglethe enclosure wthout upsetting thestraightforward look.
An extra large living room havingtwo openings at one end and win-dow space at the other, as shown inFig. 6, may be placed so that thespeakers are against the narrowwall as shown, or against the win-dow area, depending upon furniturearrangement. There are several goodspeaker arrangements. One way re-quires three speakers. The middleand high frequency range, is coveredby the units in the corners. This isan advantage in that normally onlyrelatively small speakers can beused in these spaces. The low -frequency unit should be placedagainst the wall between the othertwo speakers. One of the crossovernetworks just described should beused. If this room had a centeropening on the shorter wall andmore corner space, an ideal arrange-ment would consist of two properlybaffled full range speaker systems.
The use of the third speaker inthe center opens the way for con-siderable debate on the best ap-proach or technique to use. The
Fig. 6-A large room using widelyspaced speakers may require a thirdspeaker in the center to improve theoverall stereo presentation and mini-mize the "hole in the middle" effect.
SEPARATEMID -RANGE
& TWEETERS/FOR EACH CHANNEL
SINGLEWOOFER
ELECTRONIC TECHNICIAN Stereo, 1959 67
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Circle 68-01 on inquiry form p. 73
center speaker can be used to elim-inate a "hole in the middle" effect.Wide spacing between the speakerson each end to accomplish evengreater directional characteristicsamplify the problems of the hole inthe middle. Since it is generallyconceded that the base frequenciesdo not have directional qualities,one school of thought is that thelogical place for the third speakeris in the center and that it shouldfurnish the low notes. This leavesthe end speakers to provide thetrue stereo effect. Still anothergroup of engineers believe that athird channel in the center con-taining bits of information frome,.ch of the end channels will notonly take care of the hole in themiddle problem, but that it createsa better relationship between cen-ter stage and the other areas with-out detracting from the overallsense of lateral spaciousness be-tween one end of the stage and thtother. Fig. 7 illustrates one way totap off the third speaker so that itcan provide this information. Itshould be noted that the centerspeaker in this application does nothave to carry any appreciableamount of bass.
The L-shaped room found inmany modern homes, seemingly has
Fig. 7-Another convenient way to estab-lish a third channel. While this method doesnot add anything to the bass response, itdoes improve the directional sense with re-spect to the center of the program source.
its share of problems. One solutionis to use the principle embodied inthe single enclosure, full rangespeaker systems.
Two wide -range multiple speakers(or good extended range speakersif the budget dictates) are placedin the positions shown in Fig 8. Theobject is to have one channel feedeach major section of the room. Inthe central area of the room thetrue stereo effect is realized. Inother positions the effect is of listen-ing directly to one speaker andhearing the other one playing in an-other room. With proper balance
68 ELECTRONIC TECHNICIAN Stereo, 1959
this can be quite an effective wayof presenting stereophonic sound ina rather difficult situation.
If a room has plenty of carpetingand upholstered furniture it will notproduce many undesirable reflec-tions, and full use can be made ofa wide -range system. Recreationand other rooms having linoleum ortiled floors, painted walls and per-haps wrought iron furniture, rever-beration can be quite a problem. Infact, it becomes difficult to present
Fig. 8-The problems of the 'L" shapedroom can be overcome considerably by us-ing two wide -range multiple speaker sys-tems. Good extended range speakers may do.
a good stereo effect in a room likethis, because of the way the soundbounces around.
In such a room a good extendedrange loudspeaker may be the bestone to use, because the high fre-quencies will do little if any good.Much more care should be given tocareful angling of the units to avoidbouncing the sound directly backfrom the opposite wall. Face thespeaker units so that the sound hitsthe opposite wall at an angle. Ingeneral it might be better to con-sider another room for listeningto stereophonic sound. Recreationrooms are not necessarily the bestlistening places for high fidelitystereo or monophonic programs.
Speaker MatchingA question often asked is whether
or not to continue using an existinghigh fidelity speaker. This bringsup the question of matching speak-ers. The answers depend on thetype of existing speaker. Two ofthe large complex type speaker sys-tems each using a fairly widely sep-arated midrange and tweeter as
look what
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A complete 12 -watt hi-fi ampli-fier -preamplifier combinationin one stylish unit . . . an iat less than half the priceyou would opect to pay!
Only
$28.95
HEATHKIT
Manufacturerof the finestelectronic equipmentin kit form
BOOKSHELF 12 -WATT AMPLIFIER KITAn amplifier and preamplifier in one compact unit. The EA -2 has more thanenough power for the average home hi-fi system and provides full range fre-quency response from 20 to 20,000 CPS within tl db, with less than 1%harmonic distortion at full 12 watt output over the entire audio range (20 to20,000 CPS). IM distortion is less than 1.5% at.12 watts with low hum andnoise. EL84 tubes are used in a push-pull tapped -screen output circuit. Inputsconsist of crystal phono, tuner, and mag phono with RIAA equalization.Separate bass, treble and hum balance controls are featured. Taps providedfor 4, 8 and 16 ohm speakers. Add this unit to your present system for simplestereo conversion. Complete instructions and pictorial diagrams show whereevery part goes and assures you of quick, easy assembly. Handsome vinylclad steel cover measures 121/2" W. x 8K6' D. x 43/8' H. Neon pilot light onfront. Shpg. Wt. 15 lbs.
many more kitsto choose from!
Send for this free catalogdescribing over 100easy -to -build kits inhi-ri-test-marine andamateur radio fields.
HEATH COMPANYBenton Harbor 18, Mich.
bsidiary of Daystrom, Inc.
name
address
city & state
Circle 69-01 on ingLiry form p. 73ELECTRONIC TECHNICIAN Stereo, 1959 69
used in some hi-fi installations, arenot advisable for stereophonic pre-sentation. They confuse the soundtoo much. It is better to use thewell -integrated type. It is particu-larly important for the mid -rangeand tweeter units to be as close to-gether as possible. Even in the ex-ample illustrated in Fig. 3, wherethe tweeter is directed along a dif-ferent line from the mid -range unit,they should be mounted close to-gether so that the areas fed by theseunits will not receive the impres-sion of any noticeable separationbetween the sounds from its partic-ular channel.
Another important considerationis the question of speaker phasing.First, it is particularly important tohave the speakers in the same en-closure correctly phased so there isno dissociation effect at the cross-over frequency. This can best bechecked by playing a single channeland listening critically. Connect thetweeter first one way, then another.Listen for smoothest response andthe best sense of integration. Useprogram material such as a solovoice. The same method can be re-peated for the woofer and mid-range. Here particular attentionshould be given to the smoothestfill-in of frequencies around 250
SOLOIST SHOULDSOUND HERE
0 Of
EQUAL DISTANCE
WAWA
LISTENERSTANDHERE
,f ----
Fig. 9-A soloist's voice will appear tocome from the center when the speakeroutput is properly phased and balanced.
cycles, or whatever crossover isused.
If multiple speaker systems areused in each channel, it is essentialthat each bank of speakers in thechannel be properly phased beforeattempting to check the phase ofthe overall stereo system. A simplemethod is to try reversing the con-nection to any one channel's speak-ers to discover which gives the bestsense of position for solo program.Select a program where the soloistis intended to be approximately inthe middle, and listen from a centralpositions as shown in Fig. 9. Thething to listen for when the two
speakers are operated at the samelevel is the soloist's voice. It shouldappear to come from a point mid-way between the two speakers. Ifthe sound seems to get lost in theroom, try reversing the connectionsto one speaker. If the system useswoofers in both channels, the lowfrequencies can also be helpful, ifeach channel is correctly phasedwithin itself.
Contrary to instructions on phas-ing which have appeared in printfrom time -to -time, speakers foreach channel of a stereo systemshould be phased when listening tothe desired stereo program, and notwith batteries or monophonic mate-rial played over both channels si-multaneously. This is particularlysignificant if due to the use of dis-similar amplifiers, preamplifiers or ifconditions of program material aresuch that the two channels are notin phase going into the amplifiers,the program fed to the speakers ineach channel are out of phase. Tocorrect this condition, it is simplya matter of reversing the leads go-ing from one amplifier to its speaker.This may make the speakers out ofphase in the "battery test" sense,which is exactly opposite to the cor-rect phasing situation for conven-tional monophonic listening.
STEREO PROFITS START HERE
Compatible with both stereo and monaural records Full frequency response, 20 through 20,000 cycles "Floating armature" design for increased complianceand reduced record wear. Effective mass of stylus ap-proximately 2 milligrams High compliance in alldirections-lateral compliance 4 x 10.6 cm/dyne; ver-tical compliance 2.5 x 104 cm/dyne Recommendedtracking force with professional -type tone arm 2 to 4grams Consistently high separation between channelsignals. (Specifications for Model GC -5.)
(New G -E "Golden Classic"Stereo -Magnetic Cartridge
Easier to sell ... because it's magnetic... and because it's G -E!
Stereo installations and conversions can open up a whole newfield of profitable business for you. And you can start yourcustomers converting to stereo right now-with G.E.'s new"Golden Classic" stereo -magnetic cartridge (fully compatiblewith LP monaural records). It's easy when you tell them how amagnetic cartridge can best provide the high compliance, lowdistortion, and channel separation required by the new stereodiscs. Just as important, General Electric is the name all yourcustomers know and trust.
GENERAL ELECTRICSpecialty Electronic Components Dept., W. Genesee Street, Auburn, N. Y.
Circle 70-0/ on inquiry form p. 7370 ELECTRONIC TECHNICIAN Stereo, 1959
Changers & Turntables For StereoLower Recording Level, Vertical Rumble & Arm Consideration
The controversy of record changervs. turntable now has a new slant,with the advent of stereo. The argu-ment for the turntable is the one ofsimplicity. Where the objective issmooth motion without flutter, wowor rumble, a simple mechanismshould stand the best chance ofachieving the ideal. The argumentfor the record changer is that it doeswhat a lot of people want it to do.Expert design, close quality control,coupled with precision methods,have provided record changers andturntables whose performance isquite satisfactory for stereo pur-poses.
Some high fidelity enthusiasts willnot look at changers for another rea-son; they want to keep up with thelatest developments in tonearms andpickups. The changer is not readilyadaptable for use with a variety ofarms. One major advantage theturntable has at the moment is the
ability to operate with lower styluspressure, but the changer people areworking on this and have made someprogress.
As quick as a problem is recog-nized, that is how fast the engineersand manufacturers set about tryingto lick it. The sensitivity to the verti-cal component as found in stereopickups, has spurred all facets ofthe record player industry into ac-tion. Improvements already incorpo-rated and some yet to come in thechanger and turntable field indicatethat the relative merits and argu-ments for the changer and turntablewill stay in about the same perspec-tive.
Flutter, Wow, RumbleFlutter and wow show up exactly
the same on stereo as they do onmonophonic records. Rumble, on theother hand, has another chance ofbreaking through in stereo. With a
monophonic pickup the only form ofvibration normally picked up is in ahorizontal direction.
Since stereo pickups are sensitiveto both vertical and lateral vibra-tions, rumble components now be-come a more important factor.
To help offset this problem, someof the new stereo pickups include anacoustic, or mechanical filter, toavoid picking up low frequencyvertical components. This is per-missible because in any legitimatestereo disc recording the low fre-quencies are essentially in the lateralgroove motion. Losing the verticalcomponent at low frequencies shouldnot materially deteriorate the stereoeffect, and it does filter out somevertical rumble.
Recording LevelIt is more difficult to obtain the
high percent of modulation that haslately been impressed on most
for CUSTOM HI -Fl installations your best buy is /"of PRAISED BY THE EXPERTS 1.." PRICED RIGHT FOR YOUR PROFIT
vr LIFETIME GUARANTEE on SERVICE & ADJUSTMENT
EICO FM TUNER HFT90 withprecision "eye-tronic" tuningKIT 539.95* Wired 565.95*°Less Cover, FET incl.
EICO PreamplifiersHF65A KIT $29.95, Wired $44.95.with power supply:HF65 KIT $33.95, Wired $49.95
HF61A KIT $24.95, Wired $37.95with power supply:HF61 KIT $29.95, Wired $44.95
-mmOrgor'
EICO Stereo Preamplifier HF65KIT $39.95 Wired $64.95
"(The EICO FM Tuner provides) . . . non-critical tuning, low capture ratio (6db),close -station separation, and insensitivity todrift which are unique among FM tuner kits,to the best of our knowledge . . . one ofthe best buys you can get in high fidelitykits." - AUDIOCRAFT Kit Report.
"(The EICO Master Control Preamplifier's)performance rivals that of the most ex-pensive preamps . . . All in all, here is anexample of a high level of engineering skill,which has managed to achieve fine per-formance with simple means and low cost."
- Joseph Marshall, AUDIOCRAFT.
Concerning the EICO 60 -watt Power Ampli-fier: "Listening tests confirmed the fineinstrument test results without question. OurHF-60 produced firm, well-defined bass andclear, sweet treble on the finest speakersystems available. It clipped momentaryoverloads very well and recovered quickly,and this gave listeners the impression oftremendous reserve power. In our opinion,it is one of the best -performing amplifiersextant; it is obviously an excellent buy."
- AUDIOCRAFT Kit Report.
"We believe the EICO HF 52 (50 -watt Integrated Amplifier) should prove highly satis-factory for home music systems requiring a50 -watt amplifier. At its price, either in kitform or assembled, it represents an ex-cellent value." - Hirach-Houck Laboratories.
"For those who have been looking for a well -engineered yet inexpensive power amplifier,the newly -released EICO Model HF-20 unitmight offer a simple solution to their prob-lem. Not only does this unit provide 20 wattsof power but the circuit incorporates a pre-amplifier and a variety of contra's on asingle chassis."-William A. Stocklin, Editor,
RADIO & TY NEWS.
". . . the EICO Standard (Speaker System)proved able to create a remarkable illusionof realism from all types of program mate-rial . . . String tone was reproduced with asmooth, gutty richness . . .Bass transientswere well handled . . . never any sensationof two sound sources; the speakers blendedfaultlessly . . . an eminently musical repro-ducer ... the EICO's compactness and dis-persion characteristics would suggest un-usual suitability for stereo application."
-J. Gordon Holt, Technical Editor,HIGH FIDELITY.
EICO Stereo Amplifier -Preamplifier HF81KIT $69.95 Wired $109.95
COPR CI 1958, ELECTRONIC INSTR. CO., INC.. 33.00 N. BLVD.. C. I. N. V.
EICO 60 -Watt Ultra -LinearPower Amplifier HF60with Acro TO -330 OutputTransformerKIT $72.95
EICO 50 -Watt Ultra -LinearIntegrated Amplifier HF52KIT $69.95 Wired $109.95
EICO 20 -Watt Ultra -LinearIntegrated Amplifier HF20KIT 549.95 Wired $79.95
EICO StandardSpeaker SystemHFS2
Completelyfactory builtMahogany orWalnut, $139.95Blonde, $144.95
IN STOCKat 1900 neighborhooddistributors coast to coast.
NAME
EICO, 33-00 Northern Blvd.L. I. C. 1, N. Y.Show me HOW TO SAVE 50% on top-quality equipment checked: 0 HI -Fl
0 TEST INSTUMENTS 0 HAM GEARSend FREE literature and name ofneighborhood EICO supplier.
ADDRESS
Wired $99.95 LCITY-ZONE STATE
ET -9DI
v.el3'1
17.
ELECTRONIC TECHNICIAN Stereo, 1959Circle 71-01 on inquiry form p. 73
71
Convert ANY Phonograph to
STEREOwith FANON
LOW-COST Conversion Kits Adapts Phono for both Stereo or Monaural. Improves Sound Quality of Monaural Records. Second amplifier -speaker system adds depth.With the big boom in stereo records and stereo phonographs, you can bring anyhi-fi record player up to date to play both monaural and the new stereo records.Simple to install, the new Fanon Kits offer you top fidelity for the most economicalchangeover today. Speaker -amplifier unit alone can be used with tape recorders,tuners, etc. Your customers get more for their dollars with Fanon.
FANON STK-5High fidelity 5 -tube push-pull amplifierwith one 8" woofer and one 3" tweeterin smartly designed two-tone cabinet.Separate bass, treble and volume con-trol for second channel. High fidelityceramic turnover Stereo cartridge,mounting accessories, phono jack and15 feet of extension cable included inkit.
ONLY $4995 ListSpeaker -amplifier -cable unit
(Model ST -5) $41.95 List
400471.,Or,
klAr etwookstralill
For complete specifications andinstallation instructions write now.Ask about Fanon's complete selection of Stereo phonograph systems, too!
FANON STK-4Complete high fidelity three tubeamplifier system with two 4" phasedspeakers in handsome two-tone fashion -fabric cabinet. Separate bass, trebleand volume controls for second chan-nel. Kit includes hi-fi ceramic turnover stereo cartridge, mounting acces-sories, phono jack and 15 feet of ex-tension cable to unit.
ONLY $3995 ListSpeaker -amplifier -cable unit
(Model ST -4) $31.95 List
FANON STK-10Beautifully finished, hand -rubbedmahogany, walnut or blonde cabinetcomplete with same quality compon-ents as in STK-5 above. Kit includeshigh fidelity ceramic turnover stereocartridge, accessories, phono jack and15 ft. extension cable. Ideal for con-verting consoles.
ONLY $5995 ListSpeaker -amplifier -cable unit
(Model ST -10) $51.95 List
FANON ELECTRIC CO., INC.Dept. E-9. 98 Berriman St., Brooklyn 8, N. Y.In Canada: Active Radio & TV Dist., 58 Spadina Ave., Toronto
monophonic records, onto the newstereo recordings without runninginto much more severe distortion.Consequently the stereo records sofar released are recorded at lowerlevels. From a compatibility view-point this level difference has somejustification because the addition ofthe stereo quality to a presentationmakes it seem louder than the samelevel played over a single channel.
Because the lateral component ofa stereo record is recorded at lowerlevel, a given amount of rumble willbecome correspondingly more no-ticeable. In some instances this canmean the difference between rumblethat was not heard and its becomingobjectionable. So some units thatmight have rated as acceptable formonophonic use may not be quitegood enough for stereo.
Arm PivotsAnother factor that affects arms,
whether on record changers or turn-tables, is the matter of pivot friction.Stereo records use smaller styli.Smaller styli mean that a given sty-lus pressure produces more wear.The minimum stylus pressure is de-cided by the pickup design. But ifthere is any appreciable friction inthe arm pivot, the stylus pressuremust be increased.
So, with the exception that verticalof rumble vibration now
assume a much greater importance,the effect of stereo's advent on arms,changers and turntables is mainlythat the already rigorous require-ments become just a little more so.Undoubtedly this will stimulatefurther improvements in each kindof equipment, but most of the exist-ing models can be used for stereo.
As we go to press . .
General Electric AMPLIFIERS
MS -4000 dual channel preamp/amplifieris rated at 20 watts/channel, 20 to 20,000cps ± 0.5 db, harmonic distortion 1%,hum and noise - 73 db on high levelinput, and - 40 db channel separation.
Tape, phono and tuner inputs. $169.95.Also, not shown, MS -2000 dual channelpreamp/amplifier, similar specifications,except 14 watts/channel, $129.95.
Circle 72-01 on inquiry form p. 7372 ELECTRONIC TECHNICIAN Stereo, 1959
FREE LITERATUREEvery company advertising in STEREO 1959 has literature available on its
products. In order to save you the trouble of writing to each company in-
dividually, a simplified coupon reply form is included below. Upon receipt
of your coupon, we will route your name and address to those companies
whose literature you desire. Note that each company's advertisement has
Acro-94-01Page 94-Acrosound ultra -linear II 60 -watt amplifier,wired or kit
American Microphone-68-01
Page 68-New catalog avail-able covering microphones inevery price range
Amperex-93-03Page 93-Low noise audiotubes, such as ECC83, sub-stitute for 12 AX7
Amphenol-58-01Page 58-Broadband FM an-tennas, "Inline-type" and"Turnstile"
CBS-Hytron-57-01Page 57-New Columbia CDstereo cartridge for conver-sion or replacement
Collaro-46-01Page 46-Record changer,engineered to meet rigid de-mands of Stereo
De Ro-98-01Page 98-Stereo aids, cross-over and two -channelspeaker control
Duotone-93-01Page 93-Complete line ofneedles and cartridges forLP and 78's
Eico-71 -01Page 71-Hi-fi amplifiers,preamps and speakers, wiredand kit
Electro-Voice-44-01 and 45-01Pages 44 and 45-Cartridges,speakers and enclosures forstereo installation and con-version
Erie -95-02Page 95-Audio-amplifier kit,designed for convertingphonos to stereo
Fairchild -98-02Page 98-Line of stereo com-ponents including cartridges,arms, turntables and ampli-fiers
Fanon-72-01Page 72-Low-cost conver-sion kits, including all re-quired components
Garrard -63-01Page 63-Hi-fi record changerusing stereo cartridges
General Electric -70-01Page 70-New "Golden Clas-sic Stereo -Magnetic Cart-ridge
Grommes-62-01Page 62-New line of highfidelity stereo amplifiers &turners
Harman-Kardon-100-01Page 100-New line featur-ing "Trio" stereo amplifier."Duet" stereo tuner
Heath -69-01Page 69-Hi-fi amplifier kit;catalog describes over 100other kits
Jensen -74-01Page 74-New stereo Direc-tor Speaker Systems in fur-niture and kit forms
been issued an inquiry number. Check as many numbers on the coupon
below as you wish. Fill in the coupon completely, cut it out of the maga-
zine and mail it to ELECTRONIC TECHNICIAN, STEREO 1959, 480 Lexington
Avenue, New York 17, N.Y.
Oxford -95-01Page 95-New three-wayspeaker systems and bassreflex cabinets
Philco-65-01Page 65-New completeof diamond, sapphireosmium needles; newcording tape
lineandre -
Pickering -97-01Page 97-Stanton Stereo-Fluxvalve, precision stereopickup; Unipoise arm.
Pilot Radio -53-01Page 53-New complete lineof stereo tuners, preamps,control units and amplifiers
Quam-91 -01Page 91-Line of hi-fi speak-ers, extended range, tweet-ers, woofers, coaxials
Rek-O-Kut-42-01Page 42-New Rondine turn-tables meet rigid tolerancesof stereo, assembled and inkit form
David Riemer-96-03Page 96-Quality micro-phones, cartridges, tonearms, earphones and hard-ware
R onette-91 -02Page 91-New stereo cart-ridges for both monauraland stereo high fidelity
CUT HERE
Sherwood -92-01Page 92-FM and FM -AMtuners with high sensitivitycharacteristics
Shure -99-01Page 99-Dynetic cartridgesand tone arms for bothstereo and monaural
Sonoramic-96-01Page 96-Wide-latitude re-cording tape, packed in per-manent plastic case
Taco -93-02Page 93-FM antennas avail-able in kit form and withgold anodized finish
University -61-01Page 61-Hi-fi speakers andspeaker systems stereo -matched within 1 db
Utah -51-01Page 51-High quality loud-speakers, precisely manufac-tured to close tolerances
V- M-59-01Page 59-New "Stereo-O-Matic" 4 -speed recordchanger with stereo/mon-aural switch
Winegard-96-02Page 96-Gold anodized FMantennas in high gain andnon -directional models
This coupon must be used before Dec. 31, 1958
1. Circle free literature numbers:
42-0159-0171-0193-0398-01
44-0161-0172-0194-0198-02
45-01 46-01 51-0162-01 63-01 65-0174-01 91-01 91-0295-01 95-02 96-0199-01 100-01
53-01 57-01 58-0168-01 69-01 70-0192-01 93-01 93-0296-02 96-03 97-01
2. Fill in your name and address.Mail promptly to ELECTRONIC TECHNICIAN, Stereo 1959,Ave., New York 17, N. Y.
480 Lexington
Name
Address
City Zone State
Check one:a am a: . Service Dealer ....Consumer Other
For all your hi-fi listening . . . Jensen presents these new StereoDirector* Systems with challenging performance ... in highfashion furniture ... at prices that set new standards forloudspeaker values.
, 2.Y
JENSEN DS -100 DUAL 3 -WAY SYSTEM WITH THE NEWJ
JensenSTEREO DIRECTOR*
The DS -100 dual stereo unit, in the popular lowboy, is theanswer to the buyer's demand for a complete stereo repro-
, ducer in one cabinet. This handsomely styled loudspeakersystem provides two completely independent 3 -way speaker sys-tems with 12" Flexair woofers (total of 6 speakers) which can be
used together for superior spread source monophonic sound, as wellas stereo, The two Stereo Directors, each having an 5 inch mid -channel and compression driver h -f unit, allow flexibility in cabinetplacement with maximum effectiveness in aiming the sound to thefavored listening area. Crossover frequencies 600 and 4000 cycles.32" H., 52" W., 1814" D. Available in Walnut, Tawny Ash andMahogany Net Price 369.50
HOW THE NEW JENSEN STEREO DIRECTOR WORKS ...
A pair of these Director assemblies are used in the DS -100 Dual3 -way System (illustrated above), a single assembly in the 5S-100,mounted inside on the shelf above the Flexair woofer enclosure.Chassis easily rotated without moving cabinet, has an 8" m -f unit,compression -driver tweeter, networkabove 600 cycles are reproduced by the Stereo Director assembly. Complete system is also available in kit form.
Jensen STEREO DIRECTOR letsyou place the speakers wher-ever decor dictates, square tothe wall for best appearance.You send the sound to you, in-stantly adjust for best stereo lis-tening without moving cabinet.
ABOUT JENSEN'S NEW FLEXAIR WOOFERThe new Jensen Flexair Woofers are designed to extend bass response down to very low frequencies.They have highly -damped superlow resonance at the very bottom of the audio range -16 to 20 cycles.They have an exceptional degree of linearity and are capable of a total movement of 1". In even a rela-tively small Bass-Superllex enclosure, they deliver their extreme low -frequency performance with a newlow in distortion.
JENSEN SS -100 3 -WAY SYSTEM' WITH THE NEW Jensen
STEREO DIRECTOR
Equivalent in performance to one section of the DS -100Dual Stereo system, this elegant model includes StereoDirector Chassis and 12" Flexair woofer in the JensenBass-Supertlex enclosure for smooth coverage of therange from 20 to 15,000 cycles. Adequately driven tonormal room levels with a 10 watt amplifier, Two SS -100'sare ideal for stereo in the difficult -to -arrange living room,assuring perfect sound in the favored listening area. 32"H., 21" W., 181.i" D. Available in Walnut, Tawny Ashand Mahogany. Net Price 179.95
.. BUILDING YOUR OWN STEREO SYSTEM?Use these new kits for superb sound ... finest stereo performance.
DC -3 STEREO DIRECTOR CHASSISMounts m -f and h -f units of KT -33 to makeStereo Director assembly as used in SS -100reproducers. Includes panel, base, assemblyhardware, and complete instructions.
Send forBulletin JH-1
Trademark. Patents pending.
Akf
Space speakers. suit decor... always perfect stereo.
Perfect stereowhen you listen. evenwith adjacent wall layout.
Jen Seri MANUFACTURING COMPANY6601 5. Laramie Ave., Chicago 38, Illinois
In Canada: J. R. Longstaffe Co., Ltd., TorontoDivision of The Muter Company In Mexico: Radios Y Television, S.A., Mexico D.F.
Circle 74-01 on inquiry form page 73
KT -33 BASIC 3 -WAY SYSTEM KITIncludes Flexair 12 -inch woofer,special 8 inch m -f unit, and RP -103compression h -f unit. Complete with control,crossover network, wiring cable, and fullinstructions. Impedance 16 ohms;power rating 30 watts.
74 ELECTRONIC TECHNICIAN Stereo, 1959
STEREO CATALOGSpecifications bc!sed on manufacturers' reports
For more information on these productsSEE INQUIRY COUPON ON PAGE 73& Directory of Manufacturers on Page 88
AMPLIFIERS & PREAMPSACROSOUNDUltra -Linear IISingle channel, 60 -watt am-plifier has 18 to 30,000 cpsresponse ±1 db at full 60watts. Hum is 90 db belowrated output. IM distortionless than 0.5% at 50 watts.Harmonic distortion less than1%. Damping variable 0.5 to15. Undistorted square wave.$109.50 wired; $79.50 kit.
ARKAY SA -25Dual preamp drives 25 -wattWilliamson amplifier in chan-nel 1. Output of channel 2is fed to existing monauralamplifier. IM distortion 1.8%at 20 watts. Harmonic dis-tortion 1.5%. Hum -90 db.Damping factor 16. Kit $59.95.Also, not shown, SP -6 dualpreamp/amp kit $39.95.
BELL 3030Dual preamp/amplifier, 15watts/channel, has 20 to20,000 cps response ±0.5 db.Harmonic distortion is 0.5%at 1 db below 15 watts. Hum-79 db. Dual outputs, 4, 8,16 ohms and hi -Z. $169 95.Also, not shown, Model 2221dual channel 10 -watt pre-amp/amplifier Et $129.95.
BOGEN DB212Dual preamp/amplifier, 12watts/channel, has speakerphasing switch. Response is20 to 20,000 cps ±1 db. Noiseand hum -80 db. Harmonicdistortion 0.5% at rated out-put. Chassis $115.00; enclo-sure and legs $7.50. Also, notshown, AC -10 single channelamplifier $55.00.
EICO HF-81Dual preamp/amplifier, 14watts per channel, has 10 cpsto 100 kc response ±0.5 dbat 2 watts. IM distortion 0.5%at 5 watts/channel. Harmonicdistortion less than 1%. Humand noise -75 db. Speakerimpedances 4, 8 and 16 ohms.$109.95 wired, with cover;$69.95 kit.
EICO HF-85Dual preamp and controlcenter has independent levelcontrols with built-in clutch,hum balance control. 30 dbfeedback. Response 5 to200..000 cps ±0.3 db, to 3 vrms out. Hum 75 db. IM dis-tortion 0.03% at 1 v. Har-monic distortion 0.1% at 3 v.$64.95 wired; $39.,95 kit.
FAIRCHILD 248Dual preamp consists ofstacked Model 295. Harmonicdistortion is less than 1% at1 v. Noise -85 db. Voltagegain is 60 db in phono andtape inputs. Record changerposition provides RIAA curveand rumble filter. Ganged vol-ume control. $239.50. Model245 monaural, $119.50.
FISHER X-101Dual preamp/amplifier, 20watts/channel, has 0.7% har-monic distortion at ratedoutput. IM distortion 2%.Hum and noise -80 db.Crosstalk 50 db betweenchannels. Sensitivity 2 myfor phono input. 6 pairs ofstereo inputs. 4, 8 and 16ohm outputs. 5189.50.
ELECTRONIC TECHNICIAN Stereo, 1959 75
FISHER PR -66
Dual preamp, self -powered,has no controls, is designedfor remote control. 2 inputsand 2 outputs for connectionto audio control. AC humbalance pot. Response 20 to20,000 cps ±2 db. Gain 40 db.Hum & noise -68 db. Distor-tion 0.2% for 2 v out. Cross-talk -60 db. $29.95.
GROMMES 40PG
Dual preamp/amplifier, 20watts/channel, has 20 to20,000 cps response ±0.5 db.Harmonic distortion 1%, IMdistortion 2% at rated output.Hum & noise -80 db. Push-button rumble & scratch fil-ters. $159.50. Also, not shown,Model 24PG, 12 watts/chan-nel, $99.50.
GROMMES 209
Dual preamp with dc fila-ments has 10 to 20,000 cpsresponse ±0.25 db. Harmonicdistortion 0.05%, IM distor-tion 0.1% at rated output.Hum & noise -80 db. Out-put 1 v, up to 20 v withoutoverload. $159.50. Also, notshown, Model 214 dual pre -amp priced at $99.50.
HARMAN-KARDONA-250Dual preamp/amplifier, 25watts/channel, has 20 to20,000 cps response ±1 db at20 watts. Harmonic distor-tion less than 0.5% at 20watts, IM distortion 2%. Sep-aration over 50 db. Has fil-ters, dc filaments. $179.50.Enclosure $12.50. Also, notshown, AX20 stereo, $99.95.
HARMAN-KARDONA-224
Dual preamp/amplifier, 12watts/channel, has 45 to20,000 cps response ±1 db at12 watts. Harmonic distortionless than 1%, IM 2%. Hum-80 db. Channel separationover 50 db. Separate gangedcontrols, mode switch, bal-ance control, rumble filter.$99.95. Enclosure $7.
HEATH SP -2
Dual preamp has built-inpower supply and scratchfilter. Features 2 -channelmixing and remote balancecontrol with 20 ft. of cable.Includes 6 inputs with 4 levelcontrols. Sensitivity 2.5 my.2 on -off switches, one for acreceptacles. $56.95 in kit form.
LEAK 20
Dual amplifier, 12 watts/channel, has 20 to 20,000 cpsresponse ±0.5 db. Harmonicdistortion 0.1% at 10 watts.Hum & noise -80 db. 26 dbfeedback. Input sensitivity125 my for 10 watts. $139.Also, not shown, Model 50stereo, $179; Point One pre -amp, $109.50.
MADISON FIELDING 320
Dual preamp/amplifier, 20watts/channel, has 20 to 20,-000 cps response ±0.5 db.Hum & noise -75 db. Poweris calibrated on knobs inpeak watts. Magic eye aidspre-program level settings.4, 8 and 16 ohm speaker out-puts. $169.95. Enclosure is$19.95. Also, Model 340
McINTOSH C-85
Preamp is designed for add-ing stereo to existing mon-aural system. Stereo balancecontrol permits both chan-nels to be balanced with onecontrol. Includes mode se-lector, rumble filter and rec-ord compensator. $99. Blondeor mahogany enclosure $10extra.
PILOT SM-244
Dual preamp/amplifier, 14watts/channel, has 20 to20,000 cps response ±1 db.Hum & noise -80 db. Har-monic distortion 1%, IM1.5%. Balance control, de fil-aments. $189.50. Also, notshown, SP -215 stereo pre -amp with two VU metersfor setting reference levels,$189.50.
PILOT SP -210
Dual preamp may be pow-ered from separate stereoamplifier (SA -232, $89.50;SA -260, $129.50, not shown)or separate power supply(P-10, $19.50). Response 20to 20,000 cps ±1 db. Hum &noise -80 db. Harmonic dis-tortion 0.2% at max. sensi-tivity. $89.50.
REGENCY HF-50
Single channel 50 watt am-plifier has 20 to 20,000 cpsresponse ±0.2 db. Harmonicdistortion 1%, IM distortion1%. Output 8 and 16 ohms.1.5 v input for rated output.Negative feedback circuits.Available wired at $89.50; kit$74.50.
76 ELECTRONIC TECHNICIAN S*ereo, 1959
SARGENT-RAYMENTSR -17-17
Dual preamp/amplifier 17watts/channel, has 20 to15,000 cps response ±1 db.Harmonic distortion 0.32% at17 watts, IM 1.5%. Hum &noise -70 db. Ganged con-trols. Balance control. $189.60.Also, not shown, SR -534 dualchannel 17 watt stereo am-plifier, $106.60.
11111"11Mil
H. H. SCOTT 299
Dual preamp/amplifier, 17watts/channel, has rumbleand scratch filters. Harmonicdistortion 0.8% at full power,IM 0.3%. Noise & hum -80db. DC on filaments. Phasereversing switch. $199.95.Also, not shown, 209 dualpreamp/amplifier, 15 watts/channel, $139.95.
Arms
FAIRCHILD 282
Arm wired for 4 -pin car-tridges is designed for rec-ords up to 12"; usable to 16".Operates down to 2 gramsstylus force, adjustable bythumbscrew. Self-containedarm locking detent. No armrest required. Separateground wire. Black anodizedaluminum. $42.50.
GARRARD TPA/12Arm with plug-in head re-places TPA/10 tone arm.Two leads wired for stereoto take any cartridges. Usablefor up to 16" records. Fixedlength and tracking anglepreset. Independent weightadjustment screw atop arm.Single hole mounting. Price$19.50.
GENERAL ELECTRICTM -2G
Arm, statically balanced, fea-tures 2 -step adjustment forprecise setting of trackingforce between 0 and 6 grams.Play up to 12" records. De-signed for VR-H cartridge.Built-in arm rest. Height ad-justable from % to 2W'. 1ground & 4 lead terminals.$29.95.
SHERWOOD S-4000
20 -watt amplifier with pre -amp has dual controls, re-verse and phase inversionswitches, for converting mon-aural system to stereo. Re-sponse is 20 to 20,000 cps ±1.5db at rated output. Hum &noise -80 db. Also, notshown, S-5000 dual 20 -wattpreamp/amp.
STROMBERG-CARLSONASR -433
Dual preamp/arnplifier has1% distortion at usual lis-tening levels. Controls in-clude channel selector, mas-ter volume control, and in-dividual channel controls.$119.95. Also, not shown, aresingle channel amplifiers AR -430, 431 and 432 @ $59.95,$99.95 and $119.95.
sicauxuamumuuz;zumaimaatial
GRADO
Arm of gunstock walnutwood features one-piece con-struction. One knob adjust-ment for tracking force, ±-7grams. Tracking error 0.8°Resonance 10 cps. Offsetangle 24.5%. Wired for stereocartridges. For 12" records,$29.95; 16" transcription arm$32.50.
PICKERING 196
Arm includes same designcartridge as Fluxvalve Model371. Single pivot bearing.Will mount on motorboardmeasuring only 151/2" x 151/2"Uni-mount installation em-ploys single thumbscrew andbolt. Arm rest with sablebrush keeps stylus dust free.$59.85.
REK-O-KUT S-120
Arm of tubular aluminum,die-cast zamak cartridgeshell and brass counter-weight, has 2 ball bearingraces. Plug-in shell takes 3and 4 pin cartridges. Reso-nance 12 to 15 cps. 12" stereounit $27.95. Also S-160 16",$30.95. PS -20 4 -pin lead &extra shell $5.95.
H. H. SCOTT 1030Arm with magnetic stereo
cartridge (made in conjunc-tion with London Recording)is 12.5" long. Optimum track-ing force is 3.5 grams. StylusHo 0.5 mil, output 4 my.Height adjustable 1%" to21/2". Crosstalk better than-20 db. With arm rest, hard-ware. $89.95.
ELECTRONIC TECHNICIAN Stereo, 1959 77
CARTRIDGES
ASIATIC 13TBX
Stereo ceramic plug-in turn-over cartridge has 20 to15,000 cps response. 4 ter-minals. Tracking is 5 to 7grams. Separation -25 db.Compliance 2. Output 0.5v/channel. Load 2 meg. Withholder and 0.7 mil diamond& 3 mil sapphire $20.50.Model 13TB, 2 sapphires,$7.95.
AUDIOGERSH 200
Stereo variable reluctancecartridge has 30 to 18,500 cpsresponse ±2 db. 3 terminals.Tracking force 4 to 6 grams.Crosstalk less than -20 db.Compliance 4. Output 25 myat 1 kc for 10 cm/sec. Recom-mended load 37 k. Com-pletely shielded. With 0.7mil diamond $59.50.
COLUMBIA SC -1
Stereo ceramic cartridge has30 to 16,000 cps response ±2.5db. 3 terminals. Tracking 5to 7 grams. Separation 20db. Compliance 2. Output0.4 v at 1 kc for 5 cm/sec.Load 1.2 meg. With flexiblecable, hardware and 0.8 mildiamond needle $36.25.
DUOTONE GPS80-1
Stereo ceramic cartridge has20 to 17,500 cps response ±2db. 3 terminals. Recom-mended tracking force is 6grams. Output 1 v. Com-pliance 2. Channel separation20 db. Floating needle actionnullifies pinch. With 0.7 mildiamond $31.25; sapphire $20.
.1104,4.
ELECTRO-VOICE 66DS
Stereo ceramic plug-in car-tridge has 20 to 15,000 cpsresponse. 3 terminals. Track-ing 5 to 8 grams. Compliance1.8. Output 1 v. With 0.7 mildiamond and 3 mil sapphire$19.50. Both sapphires $5.95.Mount $1. Also, not shown,21D, $32.50, PZT magnetic$16.50-$37.50.
ERIE
Stereo ceramic plug-in cart-ridge has 0.4 v output. 3terminals. Turnover design.Single ceramic element. itec-ommended tracking force5 to 6 grams. Separation 20db over most of frequencyrange. Compliance 1.7. Withdiamond and sapphire nee-dles $24.50; 2 sapphires $5.95.
FAIRCHILD 232
Stereo dual rotating coilcartridge will track 30cm/sec at 1 kc with 4 gramsof stylus force. 4 terminals.Output 3 my/channel. Im-pedance 600 ohms. Fits both1/2" and 7/16" mounting cen-ters. With extra twisted pairleads and diamond needle$49.50.
GENERAL ELECTRICGC -7
Stereo magnetic variable re-luctance cartridge has 20 to17,000 cps response. Output6 my/channel. Lateral com-pliance 3; vertical 2. Track -mg 3.5 to 7 grams. With 0.7mil diamond needle $23.95.Model CL -7 with sapphire$16.95. Model GC -5 with 0.5mil diamond $26.95.
GRADO
Stereo dynamic cartridge has5 my/channel output @ 10cm/sec. 4 terminals. 10 to35,000 cps. Tracking force 2grams. Channel separation is25 db. Compliance 8. IM dis-tortion approximately 2%.Impedance 600 ohms. Inputload over 5 k. Stylus mass1 mg. $49.50.
PICKERING 371D
Stereo magnetic cartridgehas flat stereo range response
2 db. 4 terminals. Inter -channel interference -20 db.Includes hum rejection cir-cuit. Recommended lead re-sistance 27 k to 47 k. T -guardstylus for quick replacement.With 0.7 mil diamond stylus$29.85.
RONETTE BF -40
Stereo cartridge has 20 tola,uuu cps response. Optimumtracking force 4 to 6 grams.Lateral and vertical com-pliances 3.5. Dual -elementBinofluid unit with clip -indiamond needle, Model BF -40D is priced at $18.60. ModelBF -40S with sapphire needleis $12.
78 ELECTRONIC TECHNICIAN Stereo, 1959
SHURE M3D
Stereo "dynetic" cartridgehas 20 to 15,000 cps response±3 db. 4 terminals. Channelseparation -20 db. Output 5my. Recommended load 50 k.Compliance 4. Recommendedtracking force 3 to 4 grams.DC resistance 440 ohms. With0.7 ma diamond needle $45.
SONOTONE 8T
Stereo turnover ceramic car-tridge has 20 to 12,000 cpsresponse. 4 terminals. Track-ing force 5 to 7 grams. Out-put 0.3 v. Compliance 2. Iso-lation -20 db. Recommendedload 1 to 5 meg. With 0.7 mildiamond and 3 mil sapphire$24.50; both diamond $34.50;both sapphire $14.50.
TANNOY
Stereo variable reluctancecartridge has 30 to 16,000 cpsresponse ±2 db. Output is6 to 8 my/channel. Trackingforce is 3 to 4 grams. Notrecommended for recordchangers or record playerswith heavy tracking force.With 0.7 ma diamond needle$37.
WEATHERS
Stereo ceramic cartridge has15 to 30,000 cps response.Output 0.25 v at 7 cm/sec.Recommended tracking force2 grams. Separation betweenchannels 25 db. Completelyshielded. Complete with pick-up leads, connectors. Withdiamond needle $17.50; sap-phire needle $9.75.
:HANGERS
AUDIOGERSH XS -200
Four -speed automatic andmanual changer with push-buttons has rubber mattedturntable. Intermixes 10" and12" records in any sequence.Single play and automaticspindles. $67.50. With GEcartridge, diamond needle,$86.25. Also, not shown, XM-110A manual, $37.50.
COLLARO TSC-840
Four -speed automatic & man-ual changer has 2 -piece armwith 5 -terminal plug-in head.7", 10" and 12" automaticintermix. Wow and fluttter0.25%. Counterbalanced arm.$49.50. Also, not shown, TSC-740 4 -speed, $42.50; TSC-640,4 -speed, one-piece arm, $38.50.
GARRARD RC88
Four -speed automatic andmanual changer comes withinterchangeable spindles.Plug-in head. Muting switch.With GE cartridge, diamond& sapphire, $73.80; changeralone, $54.50. Also, not shown,RC98 alone, variable speed,$67.50; RC121 automatic alone,$42.50.
GLASER-STEERS GS77
Four -speed automatic andmanual changer has stereo -monaural switch, mutingswitch, receptacle for auto-matic amplifier shut - off.Turntable pauses duringchange cycle. Intermixes33 1/3 and 45 records. Auto-matic speed selector. $59.50.45 rpm spindle $3.60.
VM 12014 -speed changer includesstereo cartridge. Stereo -mon-aural switch and jacks. Jam -proof spindle. Rumble -48db. Tracking angle variation2". 4 -pole motor. $50. As re-placement changer on metalbase pan, Model 1226, $56.Model 1202, with plug-inhead, no cartridge. $50.
For more information on these products
SEE INQUIRY COUPON ON PAGE 73
& Directory of Manufacturers on Page 88
ELECTRONIC TECHNICIAN Stereo, 1959 79
CONTROL UNITS & ADAPTERS
BOGEN STA-1
Stereo adapter permits singleknob control of both channelvolumes. Monaural - stereo.switch. Reverse and normalswitch. Left -right balanceadjustment for 2 speakers.Connects to 2 amplifiers.$13.50. Also, not shown, ST10-A adapter -amplifier, $52.50.
DYNAKIT DSC-1
Stereo control unit addscontrol facilities to pair ofpreamps. Passive network.3 controls include volume,balance and blend to fill"hole in middle" by feedinginput through both ampli-fiers. Reverse, loudness &tape switches. Kit $12.95.
CONVERSIONKITS
FANON STK-10
Conversion kit adapts anyphono to stereo. Includes 2 -way speaker system with 3"and 8" speakers, 5 -tube am-plifier. With stereo cartridge,wood cabinet jacks, leads,$59.95. Also STK-5 $49.95;STK-4 with 3 -tube amplifier,two 4" speakers, $39.95.
GARRARD SCK-1
Kit converts company's rec-ord players for stereo. Con-sists of female connectorwired with 2 leads for tonearm, audio cable for secondamplifier, cartridge shell andhardware. No soldering. ForRC 88, 98, 121 and Tmk II.$4.05. Also SCK-2 for RC121/II.
NORTRONICS SK -100Kit converts monaural taperecorders to 1/2 -track, 2 -channel stereo when properamplifiers are added. Play-back and record functions.Includes head and wired as-sembly. Crosstalk -50 db.4 my out @ 1 kc. $23.50.Also, not shown, SK -50 1/4 -track, 4 -channel $26.
DYNAMIC SA -70
Stereo adapter permits cou-pling cartridges, tape headsor tuner to 2 amplifiers. 2inputs with stereo -monauralslide selector switch. Withtwo 31" shielded leads andmolded -on pin plugs $7.50.
MARANTZ 6
Stereo adapter provides step-attenuator master volumecontrol. Selector switchchooses phono, tuner, tape,TV, extra, stereo or monau-ral. Speaker reversal switch.12 inputs, 2 recording out-puts. With 2 output cablesto preamps. $45.
H. H. SCOTT 135
Stereo-Daptor permits simul-taneous control of 2 separateamplifiers. Master volumecontrol for both channels.Function selector. Passivecircuit. Loudness control.Input 300 k, output 100 k.Reverse stereo. Record -play-back switch. $24.95.
For more infDrmation on these products
SEE INQUIRY COUPON ON PAGE 73
& Directory of Manufacturers on Page 88
REK-O-KUT SC -12
Stereo arm conversion kitincludes all parts and twosimple tools to convert com-pany's A-120 and A-160 armsto stereo. Includes plug-inhead, terminal board andbasic arm element. For 12"arm, $17.95. Model SC -16 for16" arm, $19.95.
WALCO
Complete conversion kit forhome phono includes stereocartridge, 0.7 mil diamondneedle, 4 -watt, 5 -tube ampli-fier and preamp for secondchannel, speaker in enclo-sure and related hardware.Amplifier has separate trebleand bass controls. $69.50.
80 ELECTEONIC TECHNICIAN Stereo, 1959
MICROPHONESSONOTONEModel CM -10 omnidirectionalhigh -impedance ceramic typehas 50 to 13,000 cps response.±3 db. Sensitivity -57 db.Perforated aluminum griddamping. With 7' of shieldedcable terminating in stand-ard phone plug, $19.50.
AMERICAND204 dynamic type, 70 to
ELECTRO-VOICEModel 951 cardioid crystal
SHURE
Model 535 omnidirectional
TURNER
Model L-100 crystal type, 509500 cps, -57 db output, withpushbutton, for tape record-
type, 50 to 11,000 cps, -55db, hi -Z, $49.50. 664 cardioid
dynamic, 60 to 13,500 cps,-59 db, $72.50. Model 55S
to 10,000 cps, -52 db level,with 20' shielded cable, $12.50.
ing and general purpose, $7to $24.30. D9A low impedance
dynamic, 40 to 15,000 cps,-55 db, $85. 926 omnidirec-
unidirectional dynamic, 50 to15,000 cps, -60 db, $83. Model
Model 139 multi -impedancedynamic, 60 to 10,000 cps, -52
dynamic cardioid, 100 to 7000cps, -57 db, $82.50. D22 dy-namic omni-directional, 50 to
tional crystal, 60 to 8,000 cps,-60 db, for pa and recorders,$29.50. 666 cardioid dynamic,
777 general purpose crystal,60 to 10,000 cps, -62 db, $25.Model 737A super-cardioid
db, $45. Model 98 cardioiddynamic, 65 to 11,000 cps,-52 db, $59.50; on -off switch
12,000 cps, -55 db, variable 40 to 15,000 cps, -55 db, $150 crystal, -54 db, $46. add $4.Z, $99.50.
SPEAKERS & ENCLOSURES
ACOUSTIC RESEARCHAR -2Speaker system with acousticsuspension has two 5" conetweeters, and 10" woofer with1.1 lb. Alnico magnet, reson-ant frequency 58 cps. 40 to15,000 cps. 20 to 40 watts.131/2" x 11" x 24". 8 ohms.2000 cps crossover. $96. Also,not shown, AR -1 C $185.
ARGOS TSE-1Enclosure with forward frontdesign and ducted ports has2165 cu. in. volume. Size 24" x11" x 101/2". This bookshelfarrangement can accommo-date an 8" woofer plustweeter. Covered with ribbedpyroxylin fabric. $16.50. Also,not shown, DSE-2 q $44.50.
ATLAS WT -6Outdoor coax -projectorspeaker comprises weather-proof cone type driver with6" throat coupled to individ-ual woofer horn. Separatepressure -type driver andtweeter horn. 15 watts. 140 to15,000 cps response. 8 ohms.15" bell opening, 12" depth.$34.50.
AUDIOSPEAKER 12Enclosure with wrap -aroundcloth is 4' high, takes up 1sq. ft. of floor space. Anechoicdesign. Standard model for12" speakers $79; also for 8",$59; 15", $89. Utility models,painted plywood, $39, $49 and$59. Also, not shown, Custom16 woofer, 18 cps res., ,s:9.
CLETRON C-1233Woofer -tweeter combinationwith crossover networkmounted on sounding boardcomprises 12" woofer with21 -oz. Alnico magnet and two3" tweeters. Board 16" x 20" x7". 30 to 18,500 cps. Reson-ance 35 cps. 35 watts. $50.Also, not shown, C-15PCcoax, 15", $59; C-8JC $13.
DYNAMIC S-4Speaker system with one 8"woofer, two 5" midranges andone 4" tweeter and crossovermeasures 18" x 14" x Inwalnut, mahogany or blonde.$39.50. Model S-2 with wooferand one midrange $29.50.Also, not shown, Model S-12,12" coax and 4" tweeter,$49.50.
ELECTRONIC TECHNICIAN a Stereo, 1959 81
EICO HFS-2
Speaker system completelywired and assembled is om-nidirectional. 36" x 15W x111/2". 45 to 20,000 cps flat. Hascoax with free floating coneand slot loaded split conicalhorn. 30 watts. 16 ohms.$139.95. Also, not shown,HFS-1 two way system$39.95.
ELECTRO-VOICE I A
Coronet model speaker sys-tem measures 25" x 91/2" x17%". It includes the com-pany's SP8B coax, T35V vhfdriver, X36 crossover andAT37 level control. $102. En-closure alone $35.50. Also,not shown, are speaker sys-tems Patrician IVD $1086:Centurion IV $392; Aristocrat$72.
ELECT RO-VOICE
Second channel "Stereon"speaker system eliminatesneed for full range by pro-ducing main stereo fre-quencies above 300 cps.Lower frequencies phased tomain speaker by XX3 filter.3 -way, $129.50 and $99.50.Also, not shown, enclosurekits KD1 through KD7, $118to $26.
GENERAL ELECTRICA1-401
12" golden coax speaker has40 to 15,000 cps response. 25watts. 8 ohms. 14.5 oz. Alnicowoofer magnet, 6.8 oz. fortweeter. 1500 cps crossover.Slotted plate baffles tweeter.$49.75. Also, not shown,Model 850 8" extended range,50 to 12,000 cps, 8 ohms,$10.95.
GENERAL ELECTRICAl -4066 cu. ft. distributed port en-closure is designed for 12"speakers. May be used instraight wall or corner loca-tions. 25%" x 181/4" x 311/4".Heavily lined absorbent in-terior. $64.95. Also, notshown, A1-411 enclosure, 26"x 11" x 10", 1.2 cu. ft. $35.95.
HEATH SE-1/SC-1
Speaker enclosures SC -1, leftand right models, flankequipment cabinet SE -1.Available in birch and ma-hogany. Wing speaker en-closures are open backed tohold closed systems; 16" x291/4" x 141/2" inside. Cabinet471/4" x 361/2" x 20". SE -1$149.95; SC -1 $39.95 ea.
JENSEN KT -44
4 -way speaker component kit15" woofer, 8" upper if unit,midrange and supertweeter.40 watts. 16 cps to beyondaudibility. 16 ohms. $192.50.On DC -4 ($15.95) chassis asshown, when mounted inE-200 enclosure, ($295.50)SS -200 Stereo Director (notshown), $439.50.
JENSEN DS- I 00
Dual 3 -way speaker systemhas two 3 -way Stereo Direc-tors, each with 12" woofer,8" mf, compression hf unit.Directors may be rotated tobeam sound. 32" x 52" x 181/4".20 to 15,000 cps. 30 watts/channel. $369.50. Also, notshown, SS -100 single 3 -waysystem $179.95.
KINGDOM KAL
2 -way speaker system has35 to 17,000 cps range. 14watts. 11" x 233/4" x 10".leatherette covered, $49.50. 15"brass legs $5.95. Also, notshown, Audette Senior 2 -waysystem, 35 to 17,000 cps, 221/2x 221/2 x 101/2, $69.50. Com-pass -1, 20 to 20,000 cps,$149.50.
KLIPSCH H
3 -way speaker system is de-signed to derive a thirdstereo channel from 2 soundtracks. 11" x 12" x 16". With12" woofer $198; with 8"woofer $188. Also, not shown,Model T Shorthorn, 30 to22,000 cps, $382; Deluxe Klip-schorn $785; economy model$460.
JAMES B. LANSINGD44000
Dual 3 -way system has twosets of J13 150-4C 15" woofers,375 hf drivers, 075 ring radia-tors, and dividing networks.333/4" x 241/2" x 106". $1831) and$1884. Also, not shown,D42216 system, 117/8" x 24" x12", $84.30; D130 extendedrange 15" speaker, $84.
OXFORD 3W20
3 -way speaker componentsinclude 12" woofer, 8" mid-range, 31/2" tweeter and hard-ware. To 15,000 cps. $39.OXN-31 crossover networkshown, $12.30. Also, notshown, bass reflex cabinet,33%" x 233/4" x 17", $111;C15L608 15" coax, 30 to 15,000cps, 25 watts, $43.50.
82 ELECTRONIC TECI-NICIAN Stereo, 1959
RCA SHS11Speaker system has 8"woofer -midrange and two3W' tweeters. 293/4" x 20" x16". Ebony, mahogany, oakand walnut finishes. With 25'connecting cable, $49.95 ea.Also, not shown, SHSIO cor-ner system, $49.95; SHS12bookshelf, $19.95; SHS8, $125.
RJ Super 8Speaker system with 8" fullrange speaker for bookshelfinstallation, $90.50 unfi3O^}11.$59.50 finished. 11" x 231/2" x10". Enclosure alone, $e8.50and $37 50 Also. not 0,- -Model 12-S enclosure, 24" x21" x 10", $49.50; Model 1j en-closure, 20" x 20" x 16", $56.
SONOTONE WR-8Wide range 8" speaker has55 to 1$,000 cps response. 8watts. 8 ohms. Flux density12,000 gauss. $12. Also, notshown, speaker in Capriceenclosure, 20" x 11" x 10".3/4" plywood hand finished,$53.50; CA -12A coax speaker.35 to 20,000 cps, 10 watts, 8 to16 ohms, $27.50.
STENTORIAN HF1016U10" universal speaker with30 to 15,000 cps response has35 cps cone resonance. 16,000gauss, 31/2 lb. Alcomax mag-net. Option of 4, 8 or 16 ohms.$36.50. Also, not shown, 31/2"cone tweeter T-359, 3000 to17,000 cps, 15 watts, 16 ohms,9000 gauss, $14.95.
STEPHENS BWD2 -way speaker system in-cludes relodel 120W 12"woofer ($60) with 30 -watt,30 cps resonance ratings, andModel 5 -KT toroid tweeter($49.50) with high pass filterand brilliance control. Also,enclosures from 815 book-shelf @ $48 to Eames E-3with 3 -way $595.
STROMBERG-CARLSONRF483Coax speaker, 15" woofer andtweeter, has 25 to 18,000 cpsresponse. 45 cps free airresonance. 16 ohms. $99.95.Also, not shown, RF-480 8"speaker, 18 watts, 30 to 17,000cps, $24.95; RS -461 labyrinthsystem, 2 -way, second chan-nel, 40 to 18,000 cps, $69.95.
TANNOY 15Dual concentric 15" speakeris rated at 25 watts. 15 ohms.Resonance 40 cps. Crossover1000 cps. Complete cone as-sembly may be removed forgap cleaning. Less than 2%IM products. 18,000 gauss inhf gap. Depth 9". $159.
UNIVERSITY C-1 5HCHigh compliance 15" wooferdown to free air resonance,15 cps, 800 cps cutoff. 20 watts.4-8 and 10-20 ohms. Also, notshown, UXC-123 3 -way dif-faxial, 45 to 17,500 cps, $64;HF 206 tweeter, $33; T-50high frequency horn driver,$49.50; C-12HC woofer, $49.50.
UNIVERSITY S-102 -way speaker system with12" woofer and tweeter haslow 15-20 cps resonance.1500 cps crossover. Full bassresponse down to 30 cps. 25"x 14" x 141/2". $139. Also, notshown, S-11 3 -way with 15"woofer, $245; EN-15LH mul-tiple speaker enclosure,$139.50.
UTAH C8SExpanded range 8" speaker,20 to 15,000 cps. 16 ohms.solderless terminals. $47.50.Also, not shown, are C8Rlow frequency unit (0 $54 95;C12S expanded range, $52;C12R 20 to 7500 cps, $59.95;C15R $67.50; CT5JN 5"tweeter, 3500 to 20,000 cps,$19.50.
VITAVOX DU -120Coax speaker with 12"woofer and 3" tweeter has30 to 15,000 cps response israted at 30 watts. 15 ohms.Resonance 40 to 45 cps. Cross-over 2000 cps. Tweeter haspolyester film diaphragm.External dividing networkother than capacitor not re-quired. $89.50.
WELLCOR CBC-8-- 2Bass reflex enclosure withinclined port allows floor toact as cabinet extension.Over 3 cu. ft. Cut out for 8"and 12" speakers. 221/2" x191/2" x 133/8". On swivel base.$24.45. Also, not shown, CS -12corner enclosure, 24" x 28" x21", precut 12 and 15", $72.
WHARFEDALE SFB/3Custom model 3 -way speakersystem with 12" woofer, 10"midrange and 3" tweeter hassand -filled baffle. 30-35 cpsresonance. 20 to 20,000 cps.15 ohms. 34" x 31" x 12". $199.Also, not shown, Deluxemodel $249; W/AF/1 2 -waysystem, 30" x 17" x 12", $144.50.
ELECTRONIC TECHNICIAN Stereo, 1959 83
TAPE RECORDERS
AMPLIFIER CORP. 611-D"Stereo-Magnemite" tape re-corder has battery -operatedmotor. 50 to 7500 cps. 50 dbrange. 17 lbs. 0.1% flutter.71/2 ips. 5 v out. Earphonestereo playback. In weather -tight case $445. 611-C, 33/4 ips,100 to 3000 cps, $405; 611-E,50 to 15,000 cps, $475.
BELL T-203/RP-120Tape transport (T-203) withmonaural and stereo inlineand offset erase/record-play-back heads is $139.95. Withtwo RP -120 record -playbackpreamps, $59.95 each, re-sponse is 20 to 10,000 cps ±2db. Sensitivity 0.001 v onmike. 5 v out. 50 db S/N. 1%distortion.
BERLANT-CONCERTONE33-22 -channel stereo tape re-corder includes separateerase on each channel. 71/2and 15 ips. 55 db S/N. 40 to15,000 cps at 15 ips. 0.1%flutter and wow. $995. Also,not shown, Model 63 dualrecord and playback stereo,$695; with case $755.
0011:000:0 0 0 .°1111111111111111111
BOGEN TR-30Tape recorder designed forhalf-track monaural record-ing and stacked stereo play-back. Built-in dual preamps.71/2 and 15 ips. 50 db S/N at3% distortion. 40 to 15,000 cpsat 15 ips; 50 to 10,000 cps at71/2 ips. 3 motors. Takes 101/2"reel. About $400.
CROWNImperial model tape recorderwith monaural record andstereo inline playback pro-vision takes up to 101/2" reels.Two tracks. 30 to 15,000 cps
db at 71/2 ips. 0.15% flut-ter. 52 db S/N. $535. Alsoavailable, not shown, Stereo -X for stereo record.
PENTRONStereo tape playback andmonaural recorder plays 4 -track RCA tape cartridgewhich snaps into position,eliminating conventionalreels. 33/4 and 71/2 ips. 40 to15,000 cps. Separate preampfor each channel. VU meter.Auto shutoff. Index counter.$269.50.
PENTRON NL-4Dual channel unit recordsand plays back 2- & 4 -trackstereo. 40 to 15,000 cps at 71/2ips; 40 to 10,000 cps at 33/4 ips.50 db S /N. Flutter 0.3%. 8speakers. $349.95. ES -2 speak-ers $59.95. RC -6 remote con-trol $9.95. Not shown, NL-1Sstereo $139.95.
ROBERTS 90-SDual channel unit plays backstereo and records stereofrom broadcasts and stereorecordings. Hysteresis -syn-chronous drive motor. 40 to15,000 cps ±2 db at 71/2 ips;40 to 7500 cps ±2 db at 33/4ips. Dual remote speaker out-puts. $325.
SUPERSCOPE DK-555ADual channel unit records -and plays back stereo. 30 to16,000 cps at 71/2 ips. 30 to10,000 cps at 33/4 ips. Flutterand wow 0.2%. 2% harmonicdistortion. 4 watts output.Stacked heads. -50 db cross-talk. With 2 Sony mikes$525. Portable case $70.
V -M 750Tape recorder plays backstereo and records monaural.45 db S/N ration. 5 watts out-put. 0.4% flutter and wow.71/2 and 33/4 ips. Storage com-partment for 16 reels plusaccessories. $275. Also, notshown, Model 714, playsstacked and staggered tapes,$225.
84 ELECTRONIC TECHNICIAN Stereo, 1959
TUNERS
ARKAY ST -11
Tuner provides simultaneousFM/AM reception. FM sensi-tivity 4µv for 20 db quieting.Hum -65 db. 20 to 20,000 cps±0.5 db. Distortion 1%. Se-lectivity 200 kc 6 db down.$49.95 kit, $74.50 wired. Also,not shown, FM -8 tuner,$39.95 kit, $59.95 wired.
BOGEN RB115
FM/AM tuner with singlechannel preamp and 15 wattamplifier has 20 to 20,000 cpsresponse ±1 db. Distortion2%. FM sensitivity 3.5 Av for30 db quieting. Selectivity180 kc, 3 db. $149.50. Enclo-sure $7.50. Also, not shown,TC-100 FM/AM tuner $87.50.
BOGEN T661
FM/AM tuner has FM sen-sitivity of 2.5 Av for 30 dbquieting, 300 ohm antenna.Selectivity 180 kc, 3 db down.20 to 18,000 cps ±0.5 db. Dis-tortion 1.5%. Hum -60 db.$129.50. Enclosure $6. Also,not shown, RB-140 FM/AMtuner -amplifier $249.50.
CHAPMAN S -5E
FM/AM/SW tuner has 2 i-fstages. Sensitivity 4 Av onFM for 20 db quieting. Selec-tivity 200 kc, 3 db down. EM -81 tuning eye. Tuning rangesare 1.1-3.3 mc, 3-8.5 mc, 8.1-23 mc, 88-108 mc, and 545-1600 kc. High and lowimpedance autputs. $149.95.
DYNAMIC AF-250PA
FM/AM tuner with built insingle channel preamp and12 watt amplifier has 11tubes. 20 to 20,000 cps res-ponse. Loudness, bass, trebleand function controls. $129.50.AF -250 without preamp,$119.50. Also, not shown,T2000 FM/AM tuner alone,afc, $99.50.
EICO HFT 90
FM tuner with laavelingneon indicator has 20 to20,000 cps response ±1 db.Sensitivity 2.5 my for 30 dbquieting. I -F bandwidth 260kc, 6 db down. Hum -60 db.Maximum drift 20 kc fromcold start. Kit with frontend wired $39.95; wired$65.95. Enclosure $3.95.
FISHER 101-R
FM/AM tuner has 20 to20,000 cps response ±1 db.FM sensitivity 2.2 Av for 30db quieting. I -F bandwidth180 kc, 3 db down. 60 dbsignal/hum. Crosstalk -80db. Separate FM and AMindicator. $229.50. Also, notshown, Model 90-T FM/AMwith preamp $239.50
GROMMES 120GAT
FM/AM tuner with singlechannel preamp and 20 wattamplifier has 20 to 20 cpsresponse ±1 db. 1% har-monic distortion, 2% IM. FMsensitivity 2 Av for 20 dbquieting. Selectivity 250 kc,6 db down. Amplifier humand noise -130 db. Filters.$169.50.
GROMMES
FM tuner with electroniceye, afc, two i-f stages andtwo limiters has 20 to 20,000cps response ±0.5 db. Sen-sitivity 1µv for 20 db quiet-ing. 2% IM and 1% harmonicdistortion. Hum & noise -60db. $79.50. Also, not shown,102GT, FM/AM, $119.50.
HARMAN-KARDONT-224
"Duet" FM/AM tuner withseparate channels for each,30 to 15,000 cps ±0.75 db.Sensitivity 3.5 my for 20 dbquieting. Selectivity 240 kc,6 db down. Drift 5 :5c max.IM 0.5%. Hum -60 db.$114,95. Also, not shown,TX20 single channel FM/AM,$99.95.
HARMAN-KARDONTP200FM/AM tuner with dual pre -amps has 12 operating con-trols. Separate FM and AMsections. Indexer identifiesFM/AM station pairs. 15 to30,000 cps ±0.5 db. 0.3% IMand harmonic. Hum -80 db.Crosstalk -50 db. $189.95.Also, not shown, T-250 tuner1139.95.
ELECTRONIC TECHNICIAN Stereo, 1959 85
HEATH PT -1FM/AM tuner has 16 tubes,afc and AM variable band-width control, 15 kc on nar-row, 35 kc on broad, 6 dbdown. 300 kc i-f band forFM. 600 kc FM discrimina-tor. I -F strip consists of twoprinted circuit boards. Kitform, front end prewired,$89.95.
MADISON FIELDING 330FM/AM tuner with twochannels has tuning indica-tor for simultaneous tuningof FM and AM. 20 to 20,000cps ±1 db. I -F bandwidth420 kc, 6 db down. AFC. AMsensitivity 15 1,v per meterloop. $149.95. Enclosure$149.95 in mahogany, walnut,blonde.
McINTOSH MR -55FM/AM tuner has afc, 20 to20,000 cps response ±3 db.FM sensitivity 3µv at 100%modulation. 4 i-f stages. 2limiters. Hum -75 db. Drift30 kc without afc. Captureratio 1 to 0.8. AM distortion1%. Whistle filter. $249. En-closure $25.
PILOT FA -680FM/AM tuner for simultan-eous reception has separateAM and FM tuning meters.3 i-f stages, 2 limiters. Sen-sitivity 1µv with 30% modu-lation for 20 db quieting.1 kc wideband detector eli-minates afc. $199.50. Also, notshown, FA -690 FM/AMtuner, $179.50.
URN TAbt. t
COLLARO 4TR2004 -speed turntable has 4 -polemotor isolated by 3 tensionsprings parallel to unit plate.Bearing with steel ball takestotal thrust. Shuts off eachtime before changing speed.Black rubber mat. $49.50.Also, not shown, manualplayer TP59, 4 speeds, $29.50.
PILOT FA -690FM/AM tuner with dualpreamp has 2 tuning meters,and other specifications sim-ilar to Model FA -680. Pre -amp ratings for each channelare 20 to 20,000 cps ±1 db,output 1 v, hum and noise-80 db below 1 v, 02%harmonic distortion. $269.50.
SARGENT-RAYMENTSR -380FM/AM tuner witn dualpreamp 20 to 20,000 cps re-sponse ±1 db. Sensitivity onFM 3µv for 20 db quieting.Harmonic distortion 0.17%for 1 v out. Hum -75 db.Rumble and scratch filters.Cathode follower outputs.Carbon deposited resistorsin preamp. $189.60.
H. H. SCOTT 330-CFM/AM tuner has sensitivityof 2µv for 20 db quieting.Includes tuning meter andvernier tuning controls. AGC.Separate channels. 2 limiterstages. $209.95. Also, notshown, are Model 300FM/AM tuner with singlechannel preamp $167.95; 310-B FM $178.45.
SHERWOOD S-2000FM/AM tuner has 20 to20,000 cps response ±0.5 db.Sensitivity on FM L8 Av for30 db quieting. IM 0.25% at100% modulation, 400 cps.Hum -60 db. AFC. 2 v out.$139.50; with case $144.50-$154.50. Also, not shown,S-2000 FM tuner $99.50 with-out case.
119010511511.f
STROMBERG-CARLSONSR -440FM/AM tuner has 20 to20,000 cps response. FM sen-sitivity 1.8 uv for 20 dbquieting. I -F bandwidth200 kc. 11 tubes. AM band-widths 15 kc in broad posi-tion, 7 kc in sharp. Lowimpedance cathode followeroutput. $159.95 without topcover.
COMPONENTSFour -speed turntable has33 1/3 pulley; others inter-changeable. Noise -60 db.Wow and flutter 025%. Speedaccuracy 0.5%. 4 -pole induc-tion motor. Professional Jr.,$39.50. Extra pulleys $2.50.Base $10. Also, not shown,Models PBT & PBT4, $99.50& $109.
86 ELECTRONIC TECHNICIAN Stereo, 1959
CONNOISSEURThree -speed turntable withcontinuously variable speeds,±2% around each speedrange. Wow less than 0.15%of rated speed. Rumble bet-ter than -50 db at 7 cm/secand 500 cps. 12" non-mag-netic table. Synchronous hys-teresis motor. With Mark IItone arm $110.
FAIRCHILD 412-4Four -speed turntable haselectronic control regulatorconsisting of variable fre-quency oscillator/amplifler,which drives motor; speeddetermined by control fre-quency, adjustable ±5%.$229.50. Two speed withoutelectronic regulator, $129.50;one speed, $99.50.
GARRARD 4HFFour -speed turntable is var-iable around each speed. 12"table. Automatic start -stop inarm rest. Lift arm to start;replace to stop. $59.50. WithGE cartridges, $68.45 to$83.45. Also, not shown, 301turntable only @ $89; ModelT complete $56.45.
PICKERING 800Single -speed 331/3 rpm floatson air cushion. Vertical pe-riod of spring suspensionbelow 5 cps. Noise -65 db.Speed accuracy ±0.2%. Built-in precision leveling indi-cator. Foam rubber mat.Plays 7" to 12" records. $59.85.Bases available at $7.50 and$12.
PRESTO T -18AThree -speed turntable has11 7/8" table. Speed selectorhas 5 positions, two offs in-cluded. Wow and flutter0.2%. Rumble -47 db. With4 -pole induction motor $75.T-18-AH with hysteresismotor $131. Also, not shown,T-2 @ $59.50.
REK-O-KUT B -12HThree -speed turntable re-quires no external 45 adapter.Neon light on -off indicator.Noise -57 db. Strobe discaffixed. With hysteresis syn-chronous motor $129.95. Sim-ilar Rondine B-12GH $99.95.Also, not shown, B-12 @$84.95; N -33H @ $69.95; L-34and L-37 @ $59.95.
REK-O-KUT K33Single -speed 33 1/3 rpm turn-table with 4 -pole inductionmotor has built-in strobe forchecking speed. Table ta-pered for easy disc handling,made of lathe turned alumi-num. Noise -47 db. Comesin kit form, requiring about30 minutes for assembly.$39.95.
H. H. SCOTT 710-AThree -speed turntable haseach speed range adjust-able by -±-5%. Expanded scaleontie.,1 strobe. Rumble -60db. Wow and flutter 0.1%.Machined aluminum castingtable. Slip clutch for cueing.Induction motor. Helicaldrive gears in oil transmis-sion. $139.95.
STROMBERG-CARLSONPR -499Continuously variable turn-table from 14 to 80 rpm has4 -pole motor. Stroboscopicwindow pilot light. Noiselevel -55 db. Wow 0.18%rms. Flutter 0.1% peak, 0.01%rms. Elastic drive belt. Deckprovided with legs for oper-ation without base. $99.95.
THORENS TD -134Four -speed turntable withtranscription arm has ad-justment provision for speed.With line cord and shieldedcable $59.95. Wood base $9.Also, not shown, TD -184 withdialing arrangement to setarm on disc's lead-in groove,priced at $74.95.
WEATHERSSingle -speed 331/3 rpm turn-table kit comes up to syn-chronous speed in 3/4 of arevolution. Conical springshock mounting isolate turn-table from table vibrations.Turntable pad touches outerrim of discs, not grooves.Small 12 -pole synchronousmotor. $34.50.
For more information on these products
SEE INQUIRY CARD ON PAGE 73
& Directory of Manufacturers on Page 88
ELECTRONIC TECHNICIAN Stereo, 1959 87
STEREO BUYERS DIRECTORYManufacturers grouped in 12 product categories
1 -AMPLIFIERS, PREAMPLIFIERS,& CONTROLS
Amplifiers, 1 -channel 1
Amplifiers, 2 -channel 2
Control Units, stereo 3Preamplifiers, 1 -channel 4Preamplifiers, 2 -channel 5
Acro Products Co., 369 Shurs Lane, Philadel-phia 28, Pa. -1-2-4-5
Allied Radio Corp., 100 N. Western Ave.,Chicago 80, 111,1-2-3-5
Altec Lansing Corp., 1515 S. Manchester Ave.,Anaheim, Calif. -1-2-3-4-5
Ampex Audio, Inc., 1020 Kifer Rd., Sunnyvale,Calif. -1-5
A.R.F. Products, Inc., 7627 Lake St., RiverForest, 111.-1
Arkay Radio Kits, 120 Cedar St., New York6 N.Y.-1-2-3-5
Barker Sales Co., 339 S. Broad Ave., Ridge-field, N.J.-1-4
Bell Sound Systems, 555 Marion Rd., Colum-bus 7, Ohio -1-2-4
Blonder -Tongue Labs., 9 Ailing St., Newark2, N.J.-1-4
Bogen Co., David, P.O. Box 500, Paramus,N.J.-1-2-3-4-5
Brand Products Inc. (Madison Fielding), 11 Lor-imer St., Brooklyn 6, N.Y.-2-5
British Industries Corp. (Leak) 80 Shore Rd.,Port Washington, N.Y.-1-2-4-5
Capehart Co., 216 W. 14 St., New York 11,N.Y.-1-2
Components Corp., 106 Main St., Denville,N.J.-5
Cook Laboratories, Inc., 101 2 St., Stamford,Conn. -1-2-4-5
DeRo Electronics. 134 Nassau Rd., Roosevelt,L.I. N.Y.-3
DeWald Radio, Div. United Scientific Labs.,35-15 37 Ave., Long Island City 1 N.Y.-1-2
Dynaco Inc., 617 N. 41St., Philadelphia 4,Pa. -3
Dynamic Electronics -New York Inc., 73-39Woodhaven Blvd., Forest Hills, L.I., N.Y.-1-2-3-4
Electron Enterprises, 6917 W. Stanley Ave.,Berwyn. 111,1-2
Electronic Applications, 194 Richmond HillAve., Stamford Conn. -2
Electronic Development Associates, 126 E. 46St., New York 17, N.Y.-1-2-4-5
Electronic Instrument Co. (Eico), 3300 North-ern Blvd., Long Island City 1, N.Y.-1-2-4-5
Electro-Voice, Inc., Buchanan Mkh.-3Ercona Corp., 16 W. 46 St., New York 36,
N.Y.-1-2-3Erie Resistor Corp., 644 W 12 St., Erie 6, Pa. -1Fairchild Recording Equipment Corp., 10-40
45 Ave., Long Island City 1, N.Y.-1-2-4-5Fannon Electric Co., 98 Berriman St., Brook-
lyn 8, N.Y.-1-2-3Fen -Tone Corp., 106 5 Ave., New York 11,
N.Y.-1-2-4-5General Electric, Specialty Electronic Compo-
nents Dept., W. Genesee St., Auburn, N.Y.-1-4
Greene Co., L. Charlton, 314 Washington St.,Newton 58, Mass. -1
Harman-Kardon Inc., 520 Main St., Westbury,N.Y.-1-2-3-4-5
Heath Co., Benton Harbor, Mich.1-3-4-5Lafayette Radio, 165-08 Liberty Ave., Jamaica
33, N.Y.-1-2-3-4-5McIntosh Lab. Inc., 2 Chambers St., Bing-
hampton, N.Y.-1-3-4-5Marantz Co., 25-14 Broadway, Long Island
City 6, N.Y.-1-3Musical! Corp., 4512 W. Jefferson, Los Angeles
16, Calif. -1-2-4-5Newcomb Audio Products Co., 6824 Lexing-
ton Ave., Hollywood 38 Calif. -2Nortronics Co., 1015 S. 6 St., Minneapolis 4,
Minn. -1-2-3-4-5Pentron Corp., 777 S. Tripp Ave., Chicago 24,
111,4-5Permoflux Products Co., 4101 San Fernando
Rd., Glendale 4, Calif. -1-2-4-5Pilot Radio Corp., 37-06 36 St., Long Island
CityCo.,
.Y.-1-2-3-4-5CPowers 1.1., 1317 S. 5 Ave., Maywood,
111,1-2Precise Development Corp., 2 Neil Court,
Oceanside. N.Y.-1-2-4
Precision Electronics Inc., (Grommes) 9101King St., Franklin Park, 111,1-2-3-4-5
Radio Music Corp. 84 S. Water St., PortChester, N.Y.-1-2-4-5
Regency Div., Idea Inc., 7900 Pendelton Pike,Indianapolis 26, Ind. -1-4
Roberts Electronics, 1028 N. LaBreo Hollywood38, Calif. -5
Sargent-Rayment Co., 4926 E. 12 St., Oakland1, Calif. -2-5
Scott Inc., 1-1.H., III Powder Mill Rd., May-nard, Mass. -1-3-4-5
Setchell-Carlson, Inc., New Brighton, St. Paul12, Minn. -2
Sherwood Electronics Labs., 4300 N. Calif.Ave., Chicago 18, 111.-1
Simpson Mfg. Co., Mark, 32-28 49 St., LongIsland City 3, N.Y.-)
Stromberg-Carlson, Special Products Div., 1400N. Goodman St., Rochester 3, N.Y.-1-2-4-5
Tannoy (America) Ltd., P.O. Box 177, E. Nor-wich, L.I., N.Y.-1-4
Tech Master Corp., 75 Front St., Brooklyn 1,N.Y.-1-2-3-4-5
Telectro Industries Corp., 35-16 37 St., LongIsland City 1, N.Y.-1-2-3-4-5
Universal Woodcrafters Inc., La Porte, Ind.1-2-4-5
Video Instruments Co., 3002 Penna. Ave.,Santa Monica, Calif. -1-2-4-5
Weathers Industries, 66 E. Gloucester Pike,Barrington, N.J.-2
Webcor, Inc., 5610 W. Bloomingdale Ave.,Chicago 39, 111,3
Webster Electric Co., 1900 Clark St., Racine,Wis.-I-2-4-5
Wells -Gardner & Co., 2701 N. Kildare Ave.,Chicago 39, 111,1-2-3-4-5
Whitley Electronics, Inc., 411 S. Chauncey St.,Columbia City, Ind. -I -3
2 -CARTRIDGES, STEREO PHONOAmerican Microphone Mfg. Co., 412 S. Wy-
man St., Rockford, Ill.Astatic Corp., Harbor & Jackson Sts., Con-
neaut, OhioAudiogersh Corp., 514 Broadway, New York
12, N.Y.Barker Sales Co., 339 S. Broad Ave., Ridge-
field, N.J.Berger Communications, 109-01 72 Rd., For-
est Hills N.Y.CBS-Hytron, 100 Endicott St., Danvers, Mass.Duotone Co., Locust St., Keyport, N.J.Electra -Sonic Lobs., 35-54 36 St., Long Island
City 6, N.Y.Electro-Voice, Inc., Buchanan, Mich.Ercona Corp. 16 W. 46 St., New York 36,
N.Y.Erie Resistor Corp., 644 W 12 St., Erie 6, Pa.Fairchild Recording Equipment Corp., 10-40
45 Ave., Long Island City 1, N.Y.Federal Electronics Sales, Federal Electronics
Bldg., Rockville Centre, L.I., N.Y.Fen -Tone Corp., 106 5 Ave., New York 11,
N.Y.General. Electric Specialty Electronics Compo-
nents Dept., W. Genesee St., Auburn, N.Y.Heath Co., Benton Harbor, Mich.Jensen Industries, 7333 W. Harrison St., For-
est Park, Ill.Lafayette Radio, 165-08 Liberty Ave., Ja-
maica 33, N.Y.Miller Mfg. Co., M A., 4 & Church St., Lib-
ertyville, Ill.Pickering & Co., Sunnyside Blvd., Plainview,
L.I., N.Y.Radio Music Corp., 84 S. Water St., Port
Chester, N.Y.Recoton Corp., 62-35 Barnett Ave., Long
Island City 4, N.Y.Ronette Sales Corp., 190 Earle Ave., Lynbrook,
N.Y.Scott Inc., H. H., 1 1 1 Powder Mill Rd., May-
nard, Mass.Shure Bros., 222 Hartrey Ave., Evanston, Ill.Sonotone Corp., Elmsford, N.Y.Tannoy (America) Ltd., P.O. Box 177, E. Nor-
wich. L.I., N.Y.Televex Co., 46 Lakeview Ave., Yonkers, N.Y.'United Audio Products, 202 E. 19 St., New
York 3, N.Y.Weathers Industries, 66 E. Gloucester Pike,
Barrington, N.J.Webster Electric Co., 1900 Clark St., Racine,
Wis.
3 -CHANGERS, TURNTABLES &ARMS
Arms 1
Changers 2Turntables 3
American Microphone Mfg. Co., 412 S. Wy-man St., Rockford, 111.-1
Astatic Corp., Harbor & Jackson Sts., Con-neaut, Ohio -1
Audiogersh Corp., 514 Broadway, New York12, N.Y.-2-3
Bogen Co., David, P.O. Box 500, Paramus,N.J.-3
British Industries Corp. (Garrard), 80 Shore Rd.,Port Washington, N.Y.-1-2-3
Components Corp., 106 Main St., Denville,NJ. -3
Electronics Applications, 194 Richmond HillAve., Stamford, Conn. -3
Electro-Sonic Labs., 35-54 36 St., Long IslandCity 6.Y.-1
Corp.,CErcona 16 W. 46 St., New York 36,N.Y.-1-2-3
Fairchild Recording Equipment Corp., 10-4045 Ave., Long Island City 1, N.Y.-1-3
Fen -Tone Corp., 106 5 Ave., New York 11,N.Y.-2
General Electric, Specialty Electronic Compo-nents Dept., W. Genesee St., Auburn, N.Y.-)
Glaser-Sieers Corp., 20 Main St., Belleville 9N.J.-2
Heath Co., Benton Harbor, Mich. -3Lafayette Radio, 165-08 Liberty Ave., Ja-
maica 33, N.Y.-1-2-3Metzner Eng'g Corp., 1041 N. Sycamore Ave.,
Hollywood 38, Calif. -3Pickering & Co., Sunnyside Blvd., Plainview,
L.1., N.Y.-1-3Radio Eng'g Co., Inquirer Bldg., Philadelphia
30, Pa. -2Radio Music Corp., 84 S. Water St., Port
Chester, N.Y.-1-3Rek-O-Kut Co., 38-19 108 St., Corona 68,
N.Y.-1-3Riemer Co., David, (Rystl), 601 W. 26 St..
New York 1, N.Y.-)Rockbar Corp., (Collaro), 650 Halstead Ave.,
Mamaroneck, N.Y.-2Ronetto Sales Corp., 190 Earle Ave., Lyn-
brook, N.Y.-1Scott Inc., H. H., 111 Powder Mill Rd., May-
nard, Mass. -1-3Shure Bros., 222 Hartrey Ave., Evanston, 111.-1Smolin Labs. Woodbrook Dr., Springdale, Conn.
-2Stromberg-Carlson, Special Products Div., 1400
N. Goodman St., Rochester 3, N.Y.-1-2-3Thorens Co., Thorens Ave., New Hyde Park,
N.Y.-2-3United Audio Products, 202 E. 19 St., New
York 3, N.Y.-2V -M Corp., Benton Harbor, Mich. -2Weathers Industries, 66 E. Gloucester Pike,
Barrington, N.J.-3Webcor, Inc., 5610 W. Bloomingdale Ave.,
Chicago 39, 111.-2
4 -CONVERSION KITSStereo Phono 1
Stereo Tape Recorder 2
Allied Radio Corp., 100 N. Western Ave., Chi-cago 80, 111.-1
Altec Lansing Corp., 1515 S. Manchester Ave.,Anaheim, Calif.-)
American Electronics, Inc., 9449 W. JeffersonBlvd., Culver City, Calif. -2
Ampex Audio Inc., 1020 Kifer Rd., Sunnyvale,Calif. -1-2
A.R.F. Products, Inc., 7627 Lake St., RiverForest, 111.-1
Audiogersh Corp., 514 Broadway, New York 12,N.Y.-1
Blonder -Tongue Labs, 9 Ailing St., Newark2, N.Y.-1-2
Bogen Co. David, P.O. Box 500, Paramus,N J.-1
British Industries Corp., 80 Shore Rd., PortWashington, N.Y.-1
88 ELECTRONIC TECHNICIAN Stereo, 1959
Copehart Corp., 216 W. 14 St., New York 11,N.Y.-1
Components Corp., 106 Main St., Denvile,N.J.-1
Dynamic Electronics -New York Inc., 73-39Woodhaven Blvd., Forest Hills, L.I., N.Y.-1
Electron Enterprises, 6917 W. Stanley Ave.,Berwyn, 111.-1
Electronic Applications, 194 Richmond HillAve. Stamford, Conn. -2
Electronic Development Associates, 126 E. 46St., New York 17, N.Y.-1
Electrovox Co. (Walco), 60 Franklin St., E.Orange, N.J.-1
Ercona Corp., 16 W 46 St., New York 36,N.Y 2
Fonon Electric Co., 98 Berriman St., Brooklyn8, N.Y.-1
Fen -Tone Corp., 106 5 Ave., New York 11,N Y.-2
Miller Mfg. Co., M. A., 4 & Church St., Liberty-ville, 111.-1
Nortronics Co., 1015 S. 6 St., Minneapolis 4,Minn. -2
Olympic Radio & Television, 34-01 28 Ave.,Long Island City 1, N.Y.-1
Pentron Corp., 777 S. Tripp Ave., Chicago 24,111,2
Pickering & Co., Sunnyside Blvd., Plainview,L.I.' N.Y.-1
Pilot Radio Corp., 37-06 36 St., Long IslandCity 1, N.Y.-1
Powers Co., J. J., 1317 S. 5 Ave., Maywood,111.-1
Rek-O-Kut Co., 38-19 108 St., Corona 68,N.Y -1
Revere Camera Co., 320 E. 21 St., Chicago 16,111.-2
Roberts Electronics, 1028 N. La Brea, Holly-wood 38, Calif. -2
Scott Inc.. H. H., 111 Powder Mill Rd., May-nard, Moss. -1
Smolin Labs.. Woodbrook Dr., Springdale, Conn.-2
Stromberg-Corlson, Special Products Div., 1400N. Goodman St., Rochester 3, N.Y.-1
Tech Master Corp., 75 Front St., Brooklyn I,N.Y.-1
Telectro Industries Corp., 35-16 37 St., LongIsland City 1 N.Y.-1-2
Viking of Minneapolis, 9600 Aldrich Ave. S.,Minneapolis 20, Minn. -2
V -M Corp., Benton Harbor, Mich. -1-2Weathers Industries, 66 E. Gloucester Pike,
Barrington, N.J.-1Webcor, Inc., 5610 W. Bloomingdale Ave., Chi-
cago 39, 111.-1Webster Electric Co., 1900 Clark St., Racine,
Wis.-1-2Wells -Gardner & Co., 2701 N. Kildare Ave.,
Chicago 39, 111.-1Whitley Electronics, Inc., 411 S. Chauncey St.,
Columbia City, Ind. -1-2
5-MICROPHONES &ACCESSORIES
Allied Radio Corp., 100 N. Western Ave., Chi-cago 80, III.
Altec Lansing Corp., 1515 S. Manchester Ave.,Anaheim Calif.
American Geloso Electronics, Inc., 312 7 Ave.,New York 1, N.Y.
American Microphone Mfg. Co., 412 S. WymanSt., Rockford, Ill.
Astatic Corp., Harbor & Jackson Sts., Con-neaut, Ohio '
Duotone Co., Locust St., Keyport, N. J.Electronic Applications, 194 Richmond Hill
Ave., Stamford, Conn.Electro-Voice. Inc., Buchanan, Mich.Ercona Corp., 16 W. 46 St., New York 36, N.Y.Fen -Tone Corp.. 106 5 Ave., New York 11,
NY,Lafayette Radio, 165-08 Liberty Ave., Jamaica
33, N.Y.Luxo Lamp Corp., 102 Columbus Ave., Tucka-
hoe, N.Y.North American Philips Co., 230 Duffy Ave.,
Hicksville, N.Y.Riemer Co., David, (Rystl), 601 W. 26 St., New
York i N.Y.Shure Bros., 222 Hartrey Ave., Evanston, Ill.Sonotone Corp., Elmsford, N.Y.Stephens Trusonic Inc., 8538 Warner Dr., Cul-
ver City, Calif.Tannoy (America) Ltd., P.O. Box 177, E. Nor-
wich, L.1., N.Y.Turner Co., 909 17 St., N.E.. Cedar Rapids,
IowaWebster Electric Co., 1900 Clark St., Racine,
Wis.
6-NEEDLES, 0.5 OR 0.7 MILAmerican Phono Needle Co., 1 Continental
Ave., Forest Hills 75, N.Y.Astatic Corp., Harbor & Jackson Sts., Con-
neaut OhioBerge, Communications, 109-01 72 Rd., Forest
Hills, N.Y.Duotone Co.. Locust St., Keyport, N.J.
Electrovox Co. (Walco), 60 Franklin St., E.Orange, N.J.
Fen -Tone Corp., 106 5 Ave., New York 11,N.Y.
Fidelitone inc., 6415 Ravenswood Ave., Chi-cago 26, III.
General Electric, Specialty Electronic Compo-nents Dept., W. Genesee St., Auburn, N.Y.
Jensen Industries, 7333 W. Harrison St., ForestPark, Ill.
Miller Mfg. Co., M. A., 4 & Church St., Liberty-ville, Ill.
Pfonstiehl Chemical Corp., 104 Lake ViewAve., Waukegan, Ill.
Pickering & Co., Sunnyside Blvd., Plainview,L.I., N.Y.
Recoton Corp., 62-35 Barnett Ave., LongIsland C ty 4, N.Y.
Shure Bros., zn Hartrey Ave., Evanston, Ill.Televex Co., 46 Lakeview Ave., Yonkers, N.Y.Webster Electric Co., 1900 Clark St., Racine,
Wis.
7-PHONOGRAPH SYSTEMSAccessories 1
Stereo, complete 2
Admiral Corp., 3800 W. Cortland St., Chicago47, 111,2
Allied Radio Corp., 100 N. Western Ave.,Chicago 80, 111,2
Ampex Audio Inc., 1020 Kifer Rd., Sunnyvale,Calif. -2
A.R.F. Products, Inc., 7627 Lake St., RiverForest, 111.-2
Audio -Master Corp., 17 E. 45 St., New York17, N.Y.-2
Berger Communications, 109-01 72 Rd., ForestHills, N.Y.-2
British Industries Corp., 80 Shore Rd., PortWashington, N.Y.-1
Capehart Corp., 216 W. 14 St., New York II,N.Y.-2
Components Corp., 106 Main St., Denville,N.1 .-2
DeRo Electronics, 134 Nassau Rd., Roosevelt,L.I. N.Y-1
Duotone Co., Locust St., Keyport, N.J.-1Dynamic Electronics -New York Inc., 73-39
Woodhaven Blvd., Forest Hills, L.I., N.Y.-1-2Electron Enterprises, 6917 W. Stanley Ave.,
Berwyn, 111.-2Electrovox Co. (Walco), 60 Franklin St., E.
Orange, N.J.-1Emerson Radio & Phono. Corp., 14 & Coles
Sts., Jersey City 2, N.J.-2Fairchild Recording Equipment Corp., 10-40
45 Ave., Long Island City 1, N.Y.-2Fanon Electric Co., 98 Berriman St., Brooklyn
8, N.Y.-2Fen -Tone Corp., 106 5 Ave., New York 11,
N.Y -1Fidelitone Inc., 6415 Ravenswood Ave., Chi-
cago 26, 111.-1General Electric, Specialty Electronic Compo-
nents Dept., W. Genesee St., Auburn, N.Y.-1Granco Products, Inc., 36-07 20 Ave., Long
Island City 5, N.Y.-2Greene Co., L. Charlton, 314 Washington St.,
Newton 58, Mass. -1Hallmark Electronics Corp., 383 Concord Ave.,
New York 54, N.Y.-2Heath Co. Benton Harbor, Mich. -2Leslie Creations, Lafayette Hill, Pa. -IMagnavox Co., 2131 Bueter Rd., Ft. Wayne,
Ind. -2Microtran Co., 145 E. Mineola Ave., Valley
Stream, N.Y.-1Miller Mfg. Co., M. A., 4 & Church St., Lib-
ertyville, 111.-1Motorola, Inc., 4545 W. Augusta Blvd., Chi-
cago 51, 111,2Musicall Corp., 4512 W. Jefferson, Los An-
geles 16 Calif. -2Olympic Radio & Television, 34-01 28 Ave.,
Long Island City 1, N.Y.-2Philco Corp., "C' & Tioga Sts., Philadelphia
34, Pa. -2Pilot Radio Corp., 37-06 36 St., Long Island
City 1, N.Y.-2Precise Development Corp., 2 Neil Court,
Oceanside, N.Y.-2Radio Corp. of America, Cherry Hill, Delaware
Township, Camden 8, N.J.-2Recoton Corp., 62-35 Barnett Ave., Long
Island City 4, N.Y.-1Riemer Co., David (Rystl), 601 W. 26 St., New
York 1, N.Y.-1Robins Industries Corp., 36-27 Prince St..
Flushing 54, N.Y.-1Setchell-Carlson, Inc., New Brighton, St. Paul
12, Minn. -2Stevens Products, Inc., 86 Main St., East
Orange, N.J.-1Stromberg-Carlson, Special Products Div., 1400
N. Goodman St., Rochester 3, N.Y.-2Telectro Industries Corp., 35-16 37 St., Long
Island City 1, N.Y.-2United Audio Products, 202 E. 19 St., New
York 3 N.Y.-1Vidaire Electronics Mfg. Co., 44 Church St.,
Baldwin, L. I., N.Y.-1V -M Corp., Benton Harbor, Mich. -1-2Walsco Electronics Mfg. Co., 100 W. Green
St., Rockford, 111.-1
Waters Conley Co., 17 E. Chestnut St., Chicago11, 111.-2
Webcor, Inc., 5610 W. Bloomingdale Ave.,Chicago 39, 111.-1-2
Wells -Gardner & Co., 2701 N. Kildare Ave.,Chicago 39, 111.-2
Wendell Plastic Fabrics Corp., 1220 Broadway,New York 1, N.Y.-1
Westinghouse Electric Corp., Metuchen, N.J.-2Whitley Electronics, Inc., 411 S. Chauncey St.,
Columbia City, Ind. -2Zenith Radio Corp., 6001 W. Dickens Ave.,
Chicago 39, 111.-2
8-RECORDS, STEREOAudio Fidelity, Inc., 770 11 Ave., New York,
N.YColumbia Records, 799 7 Ave., New York 19,
N.Y.Components Corp., 106 Main St., Denville, NJ.Corcertapes, Inc., P.O. Box 88, Wilmette, Ill.COCK Laboratories, Inc., 101 2 St., Stamford,
Conn.Counterpoint Recordings Inc., 333 6 Ave., New
York 14, N.Y.Decca Records, 50 W. 57 St., New York 19,
N.Y.Elektra Corp., 361 Bleecker St., New York 14,
N.Y.Fidelity Distributors, 7803 Sunset Blvd., Holly-
wood 46 Calif.Hallmark Electronics Corp., 383 Concord Ave.,
New York 54, N.Y.Int.° Pacific Recording, (Omega) 854 N. Vine
St., Hollywood 38, Calif.London Records, 539 W. 25 St., New York, N.Y.Mercury Records, 35 E. Wacker Dr., Chicago 1,
111.
Radio Corp. of Americo, RCA Records Div.,155 E. 24 St., New York, N.Y.
Smolin Labs., Woodbrook Dr., Springdale, Conn.Stere-O-Craft, Div. Craft Recording Corp., 1650
Broadway, New York, N.Y.Stereo Sound Studios, 238 E. 26 St., New York
10, N.Y.Urania Records, 233 Main St., Belleville 9, N.J.Vanguard Recording Society, 256 W. 55 St.,
New York 19, N.Y.Vox Productions (Stereovox), 236 W. 55 St.,
New York 19, N.Y.Westminster Recordings Co., 275 7 Ave., New
York 1, N.Y.Zodiac Recording Co., 501 Madison Ave., New
York 22, N.Y.
9-SPEAKERS & CABINETSEnc osures & Cabinets 1
Speakers & Speaker Systems 2
Acoustic Research, Inc., 24 Thorndike St.,Cambridge 41, Mass. -2
Allied Radio Corp. (Knight), 100 N. WesternAve., Chicago 80, 111,1-2
Altec Lansing Corp., 1515 S. Manchester Ave.,Anaheim, Calif. -1-2
American Loudspeaker Div., ContemporaryAmerican Furniture, 1821 Berteau, Chicago13, 111.-1
Ampex Audio Inc., 1020 Kifer Rd., Sunnyvale,Colit.-2
A.R.F. Products, Inc., 7627 Lake St., RiverForest, ill. -1
Argos Products Co., 301 Main St., Genoa, 111.-1Arnnold Ceramics Inc., Isophon Div., I E. 57
Si., New York 22, N.Y.-2Atlas Sound Corp.. 1449-39 St., Brooklyn 18,
N.Y.-2Auciogersh Corp. (Kingdom), 514 Broadway,
New York 12, N.Y.-2Auciospeaker Laboratories, 1114 E. Emporia
St., Ontario, Calif. -1-2Barker Sales Co., 339 S. Broad Ave., Ridge-
field, N.J.-2Becker Electronic Mfg. Corp., 1091 Rockaway
Ave., Volley Stream, N.Y.-2Berger Communications, 109-01 72 Rd., Forest
Hills. N.Y.-1Blonder -Tongue Labs., 9 Ailing St., Newark 2,
NJ .-1-2Bozak Sales Co., R. T., Box 1166, Darien,
Conn. -1-2Bradford Audio Corp., 27 E. 38 St., New York
16, N.Y.-1-2British Industries Corp. (Wharfedale, R -J) 80
Shore Rd., Port Washington, N.Y.-1-2Cabinet Div., G & H Wood Products, 99 N. 11
St., Brooklyn 11, N.Y.-1Calif Cabinet Co., 522 S. Son Pedro St., Los
Angeles 13, Calif. -1Capehart Corp., 216 W. 14 St., New York 11,
NY. -1Cletron, Inc., 1974 E. 61 St., Cleveland 3,
Ohio -2DeRo Electronics, 134 Nassau Rd., Roosevelt,
L.i N.Y.-IDuotone Co., Locust St., Keyport, N.J.-1Dynamic Electronics -New York Inc., 73-39
Woodhaven Blvd., Forest Hills, L.I. N.Y.-1Electron Enterprises, 6917 W. Stanley Ave.,
Berwyn, 111.-1
ELECTRONIC TECHNICIAN Stereo, 1959 89
Electronic Applications, 194 Richmond HillAve., Stamford, Conn. -2
Electronic Instrument Co. (Eico), 3300 North-ern Blvd., Long Island City 1, N.Y.-1-2
Electro-Voice, Inc., Buchanan, Mich. -1-2Ercona Corp.. 16 W. 46 St., New York 36, N.Y.-
1-2Fourjay Industries, 2360 W. Dorothy Lone
Dayton 39, Ohio -1General Electric, Specialty Electronic Compo-
nents Dept., W Genesee St., Auburn, N.Y.-1-2
Granco Products, Inc., 36-07 20 Ave., LongIsland City 5, N.Y.-2
Greene Co., L. Charlton, 314 Washington St.,Newton 58, Mass. -1
Hallmark Electronics Corp., 383 Concord Ave.,New York 54, N.Y.-2
Hartley Products Co., 521 E. 162 St.. NewYork 51, N.Y.-2
Heath Co., Benton Harbor, Mich. -1Jensen Mfg. Co., 6601 S. Laramie Ave., Chi-
cago 38. 111:1-2Klipsch & Associates, Hope, Ark, -2KLH Research & Devel. Corp., 30 Cross St.,
Cambridge, Mass. -2Lafayette Radio. 165-08 Liberty Ave., Jamaica
33, N.Y.-1-2Lansing Sound Co., James, 3249 Casitas Ave.,
Los Angeles 39, Calif. -1-2Lowell Mfg. Co., 3030 Laclede Station Rd.,
St. Louis 17, Mo.-2Mobil Electronics Mfg. Co., 1111 State Rd.
67 E., Anderson, Ind. -1Neshaminy Electronic Corp. (JansZen) Nesho-
miny, Pa. -2North American Philips Co., 230 Duffy Ave.,
Hicksville, N.Y.-1-2Olympic Radio & Television, 34-01 28 Ave..
Long Island City 1, N.Y.-1Oxford Components, Inc., 556 W. Monroe St.,
Chicago 6, 111.-1-2Pentron Corp., 777 S. Tripp Ave., Chicago 24.
!II. -2Permoflux Products Co., 4101 San Fernando
Rd., Glendale 4, Calif. -1-2Pickering & Co., Sunnyside Blvd., Plainview,
L.I.' N.Y.-2Pilot Radio Corp., 37-06 36 St., Long Island
City 1, N.Y.-2Powers Co. J. J., 1317 S. 5 Ave., Maywood,
111,2Quam-Nichols Co., 226 E. Marquette Rd., Chi-
cago 37, 111.-2Racon Electric Co., 1261 Broadway, New York
1, N.Y.-1-2Rodin Merchandise Sales, 2016 Bronxdale Ave.,
New York 62, N.Y.-1Riemer Co., David, (Rystl), 601 W. 26 St.,
New York 1, N.Y.-2Rockbar Corp (Goodman) 650 Halstead Ave.,
Mamaroneck, N.Y.-1-2Saxton Products, Inc., 1661 Boone Ave., New
York 60, N.Y.-1Setchell-Carlsn^ Inc., New Brighton, St. Paul
12, Minn. -1-2Smolin Labs. Woodbrook Dr., Springdale,
Conn. -2Sonotone Corp., Elmsford, N.Y.-2Stephens Trusonic Inc., 6538 Warner Dr.. Cul-
ver City, Colif.1-2Stromberg-Carlson, Special Products Div., 1400
E.'Goodman St., Rochester 3, N.Y.-1-2Tandberg of Americo, 10 E. 52 St., New York
22, N.Y -2Tannoy (America) Ltd., P.O. Box 177, E. Nor-
wich L.I., N.Y.-1-2United Audio Products (Wigo), 202 E. 19 St.,
New York 3, N.Y.-2Universal Woodcrafters Inc., La Porte, Ind. -
1 -2University Loudspeakers, Inc., 80 S. Kensico
Ave., White Plains, N.Y.-1-2Utah Radio & Electronic Corp., 1124 E. Frank-
lin St., Huntington, Ind. -1-2V -M Corp., Benton Harbor, Mich. -1-2Weathers Industries, 66 E. Gloucester Pike, Bar-
rington, N.J.-1Webcor Inc., 5610 W. Bloomingdale Ave., Chi-
cago 39, 111.-2Webster Electric Co., 1900 Clark St., Racine.
Wis.-2Wellcor, Inc. 1218 N. Wells St., Chicago 10
111.-1Wells -Gardner & Co., 2701 N. Kildare Ave.,
Chicago 39, 111.-1White Inc. Stan, 725 S. LaSalle St.. Chicago
5111.-1-2Whitley Electronics, Inc., 411 S. Chauncey St.,
Columbia City, Ind. -1-2
1 0-TAPEBlank 1
2Prerecorded stereo
Audio Devices Inc., 444 Madison Ave.. NewYoek 22, N.Y.-1
Audio Fidelity, Inc., 770 11 Ave., New York,N.Y.-2
Audio -Master Corp., 17 E. 45 St., New York 17,N Y -2
Concertapes, Inc., P.O. Box 88, Wilmette, 111.-2Cook Laboratories, Inc.. 101 2 St., Stamford,
Conn. -2Counterpoint Recordings, Inc., 333 6 Ave.,
New York 14, N.Y.-2
Duotone Co., Locust St., Keyport, N.J.-1Elektra Corp., 361 Bleecker St., New York 14,
N.Y.-2Ercono Corp., 16 W. 46 St., New York 36, N.Y.
-1Ferrodynamics Corp., Gregg St. & Route 17,
Lodi, N.J. (Sonoramic)-1Fidelitone Inc., 6415 Ravenswood Ave., Chi-
cago 26, 111.-1Fidelity Distributors, 7803 Sunset Blvd., Holly-
wood 46, Calif. -2Int'l Pacific Recording (Omegatape), 854 N.
Vine St., Hollywood 38, Calif. -2Lafayette Radio, 165-08 Liberty Ave., Jamaica
33, N Y.-1Livingston Audio Products, P.O. Box 202, Cald-
well, N.J.-2Minnesota Mining & Mfg. Co., 900 Bush St.,
St. Paul 6, Minn. -1National Tape Library, 2413 Penna Ave., N.W.,
Washington 7, D.C.-2ORRadio Industries Inc. (Irish), Shamrock Cir-
cle, Opelika, Ala. -1Reeves Soundcroft Corp., 10 E. 52 St., New
York 22, N.Y.-1Smolin Lobs.. Woodbrook Dr., Springdale,
Conn -2Stere-O-Craft, Div. Croft Recording Corp., 1650
Broadway, New York, N.Y.-2Stereophony Inc., 112 Oak Plaza, St. Paul 9.
Minn. -2Stereo Sound Studios, 238 E. 26 St., New York
10, N.Y.-2Tandberg of America, 10 E. 52 St., New York
22 N.Y:iUrania Records, 233 Main St., Belleville 9,
N.J.-2Vanguard Recording Society, 256 W. 55 St.,
New York 19, N.Y.-2Vox Productions (Stereovox), 236 W. 55 St.,
New York 19, N.Y.-2Westminster Recordings Co., 275 7 Ave., New
York 1 N.Y.-2Zodiac Recording Co., 501 Madison Ave.,
New York 22, N.Y.-2
1 1 -TAPE RECORDERS, PLAY-BACKS, & ACCESSORIES
Accessories 1
Heads, stereo 2Recorders & Playbacks, stereo 3
Alonge Products Inc., 163 W. 23 St., NewYork 11, N.Y.-1
American Electronics, Inc., 9449 W. JeffersonBlvd., Culver City, Calif. -1-2-3
American Geloso Electronics, Inc., 312 7 Ave.,New York 1, N.Y.-1
American Microphone Mfg. Co., 412 S. WymanSt., Rockford, 111:2
Ampex Audio Inc., 1020 Kifer Rd., Sunnyvale,Calif. -1-3
Amplifier Corp. of America, 398 Broadway,New York 13, N.Y.-3
Audio Devices Inc. 444 Madison Ave., NewYork 22, N.Y.-1
Audiogersh Corp., 514 Broadway, New York12 N.Y.-3
Audio -Master Corp., 17 E. 45 St., New York 17,N.Y.-2
Bell Sound Systems, 555 Marion Rd., Columbus7, Ohio -1-3
Berger Communications, 109-01 72 Rd., ForestHills, N.Y.-2
Born Co. David, P.O. Box 500, Paramus, N.J.-
Columbia Records, 799 7 Ave., New York 19.N.Y.-3
Electronic Applications, 194 Richmond HillAve., Stamford, Conn. -2-3
Ercora Corp., 16 W. 46 St., New York 36, N.Y.-1-2-3
Fidelitone Inc., 6415 Ravenswood Ave., Chi-cago 26 111.-1
General Kinetics Inc., 555 23 St., S., Arlington2 Va.-1
Int'l Radio & Electronics Corp., S. 17 St. &Mishawaka Rd., Elkhart/ Ind. -3
Lafayette Radio 165-08 Liberty Ave., Jamaico33, N.Y.-3
Lipps Eng'g Edwin A., 1511 Colorado Ave..Santa Monica, Calif. -1-2
Mognecessories Box 6960, Washington 20,D.C.-1
Magnecord Div., Midwestern Instruments, P.O.Box 7186, Tulsa, Okla. -3
Morco Industries, 3rd & Franklin Sts., Womels-dc.1 P3. t
Metzner Eng'g Corp., 1041 N. Sycamore Ave.,Hollywood 38 Calif. -3
Michigan Magnetics. Inc., Vermontville. Mich. -3
Microtron Co., 145 E. Mineola Ave., volleyStream, N.Y.-1
North American Philips Co., 230 Duffy Ave.,Hicksville, N.Y.-3
Nortronics Co., 1015 S. 6 St., Minneapolis 4,Minn. -1-2
Pentron Corp., 777 S. Tripp Ave., Chicago 24III:1-2-3
Permoflux Products Co., 4101 San FernandoRd., Glendale 4, Calif. -3
Pro -Tex Reel Band, 2108 Payne Ave., Cleve-land 14 Ohio -I
Radio Corp. of Americo, Cherry Hill, DelawareTwp., Camden 8 N.J.-8
Reiter Co., F. 3340 Bonnie Hill Dr., Hollywood28, Calif. -1
Roberts Electronics, 1028 N. LaBrea, Holly-wood 38, Calif. -1-3
Robins Industries Corp., 36-27 Prince St.,Flushing 54, N.Y.-1
Saxton Products, Inc., 1661. Boone Ave., NewYork 60, N.Y.-)
Scott Instrument Lobs., 17 E. 48 St., NewYork 17, N.Y.-1
Shure Bros., 222 Hartrey Ave., Evanston, 111:2Smolin Labs., Woodbrook Dr., Springdale,
Conn. -3Superscooe, Inc., 8520 Tujungo Ave., Sun
Valley, Calif. -3Tandberg of America, 10 E. 52 St., New York
22, N.Y.-2-3Tayloreel Corp. 185 Murray St., Rochester 6,
N.Y.- iTelectro Industries Corp., 35-16 37 St., Long
Island City 1, N.Y.-1-2-3Viking of Minneapolis, 9600 Aldrich Ave. S.,
Minneapolis 20, Minn. -1-2-3V -M Corp., Benton Harbor, Mich. -1-3Walsco Electronics Mfg. Co., 100 W. Green
St., Rockford, 111.-1Webcor Inc., 5610 W. Bloomingdale Ave.,
Chicago 39 111:1-3Webster Electric Co., 1900 Clark St., Racine,
Wis.-1-2-3Wollensak Optical Co., 20 E. 21 St., Chicago
16, 111.-3
1 2-TUNERSAM or FM "single play" 1
AM & FM "simultaneous play" 2
Multiplex adaptab1e 3
Allied Radio Corp., 100 N. Western Ave., Chi-cago 80, 111.-1-2
Altec Lansing Corp., 1515 S. Manchester Ave..Anaheim, Calif. -1-3
American Geloso Electronics, Inc., 312 7 Ave.,New York 1, N.Y.-1
Ampex Audio, Inc., 1020 Kifer Rd., Sunny-vale, Calif: 2-3
Arkay Radio Kits, 120 Cedar St., New York 6,N.Y.-1-2-3
Bell Sound Systems, 555 Marion Rd., Columbus7, Ohio -1-2-3
Blonder -Tongue Labs., 9 Ailing St., Newark 2,N.J.-1
Bogen Co., David, P.O. Box 500, Paramus,N.J.-1-2-3
Brand Products Inc., (Madison Fielding), 11
Lorimer St., Brooklyn 6, N.Y.-2-3British Industries Corp., 80 Shore Rd., Port
Washington, N.Y.-1Capehart Corp., 216 W. 14 St., New York II,
N.Y.-1-3DeWald Radio, Div., United Scientific Lab., 35-
15 37 Ave., Long Island City 1, N.Y.-1-2-3Dynamic Electronics -New York Inc., 73-39
Woodhaven Blvd., Forest Hills, L.I., N.Y.-1-2-3
Electronic Development Associates, 125 E. 46St., New York 17, N.Y.-1-2-3
Electronic Instrument Co. (Eico), 3300 NorthernBlvd., Long Island City 1, N.Y.-1-3
Ercona Corp., 16 W. 46 St., New York 36,N Y.-1
Erie Resistor Corp., 644 W. 12 St., Erie 6, Pa. -1Granco Products, Inc., 36-07 20 Ave., Long
Island City 5, N.Y.-1-2Harman-Kordon Inc., 520 Main St., Westbury,
N.Y.-1-2-3Heath Co., Benton Harbor, Mich. -1Lafayette Radio 165-08 Liberty Ave., Jamaica
33, N.Y-i-2-McIntosh Lab. Inc., 2 Chambers St., Bing-
hamton, N.Y.-1-3Miller Co., J. W., 5917 S. Main St., Los Angeles
3, Calif --1-2-3Mobil Electronics Mfg. Co., 1111 State Rd. 67
E., Anderson, Ind. -3Pilot Radio Corp. 37-06 36 St., Long Island
City 1, N.Y.-1-2-3Precise Development Corp., 2 Neil Court,
Oceanside, N.Y.-)Precision Electronics Inc. (Grommes), 9101 King
St., Franklin Park, 111.-1-2-3Regency Div., Idea Inc., 7900 Pendleton Pike,
Indianapolis 26, Ind. -1Sargent-Rayment Co., 4926 E. 12 St., Oakland
1, Calif. -1-3Scott Inc., H. H. I 1 1 Powder Mill Rd., May-
nard, Mass. -1-2-3Setchell-Carlson, Inc., New Brighton, St. Paul
12, Minn. -2Sherwood Electronics Labs., 4300 N. Calif. Ave.,
Chicago 18, 111.-1Simpson Mfg. Co., Mark, 32-28 49 St., Long
Island City, 3, N.Y.-1Stromberg-Carlson, Special Products Div., 1400
N. Goodman St., Rochester 3, N.Y.-1Tech Master Corp., 75 Front St., Brooklyn I,
N.Y -1-2-3Video Instruments Co., 3002 Penna. Ave.,
Santo Monica, Calif. -1-2Wells -Gardner & Co., 2701 N. Kildare Ave.,
Chicago 39, 111.-1-3Whitley Electronics, Inc., 411 S. Chauncey St.,
Columbia City. Ind. -1
90 ELECTRONIC TECHNICIAN Stereo, 1959
Alphabetical
List of
Manufacturers(Numbers refer to sections
in which products are listed.)
Acoustic Research, Inc., 24 Thorndike St., Cambridge41, Mass. -9
Acro Products Co., 369 Shurs Lane, Philadelphia 28,Pa. -1
Admiral Corp.. 3600 W. Cortland St., Chicago 47,111.-7
Allied Radio Corp., 100 N. Western Ave., Chicago 80,111.-1-4-5-7-9-12
Alonge Products, Inc-, 163 W. 23 St., New York 11,N.Y.-11
Altec Lansing Corp , 1515 S. Manchester Ave., Anaheim,Calif. -1-4-5-9-12
American Electronics, Inc., 9449 W. Jefferson Blvd.,Culver City, Calif. -4-11
American Geloso Electronics, Inc., 312 7 Ave., New York1, N.Y.-5-11-12
American Loudspeaker Div., Contemporary American Fur-niture, 1821 Berteau, Chicago 13, 111.-9
American Microphone Mfg. Co., 412 S. Wyman St.,Rockford, 111.-2-3-5-11
American Phono Needle Co., 1 Continental Ave., ForestHills 75, N.Y.-6
Ampex Audio, Inc., 1020 Kifer Rd., Sunnyvale, Calif. -1-4-7-9-11-12
Amplifier Corp. of America, 398 Broadway. New York13, N.Y.-11
A.R.F. Products, Inc., 7627 Lake St., River Forest,111.-1-4-7-9
Argos Products Co., 301 Main St.. Genoa, 111.-9Arkay Radio Kits, 120 Cedar St., New York 6, N.Y.-1-12Arnhold Ceramics Inc., Isophon Div., 1 E. 57 St., New
York 22, N.Y.-9Astatic Corp., Harbor & Jackson Sts., Conneaut, Ohio -2-
3-5-6Atlas Sound Corp., 1449 39 St., Brooklyn 18, N.Y.-9Audio Devices, Inc., 444 Madison Ave., New York 22,
N .Y.-10-11Audio Fidelity, Inc., 770 11 Ave., New York, N.Y.-8-10Audiogersh Corp., 514 Broadway, New York 12, N.Y.-2-
3-4-9-11Audio -Master Corp., 17 E. 45 St., New York 17,
N.Y.-7-10-11Audiospeaker Labs., 1114 E. Emporia St., Ontario,
Calif. -9Barker Sales Co., 339 S. Broad Ave., Ridgefield, N.J.-1-
2-9Becker Electronic Mfg. Corp., 1091 Rockaway Ave.,
Valley Stream, N.Y.-9Bell Sound Systems, 555 Marion Rd., Columbus 7,
Ohio -1-11-12Berger Communications, 109-01 72 Rd., Forest Hills,
N .Y.-2-6-7-9-11Blonder -Tongue Labs., 9 Ailing St., Newark 2, N.J.-1-4-
9-12Bogen Co . Davrd, P.O. Box 500. Paramus, N.J.-1-3-
4-11-12Bozak Sales Co., R. T., Box 1166, Darien, Conn. -9Bradford Audio Corp.. 27 E. 38 St., New York 16,
N .Y.-9Brand Products Inc (Madison Fielding), 11 Lorimer
St., Brooklyn 6, N.Y.-1-12British Industries Corp., 80 Shore Rd., Port Washington,
N .Y.-1-3-4-7-9-12Cabinart Div. G&H Wood Products, 99 N. 11 St.,
Brooklyn 11, N.Y.-9Calif. Cabinet Co., 522 S. San Pedro St., Los Angeles
13, Calif. -9Capehart Corp., 216 W. 14 St., New York 11, N.Y.-1-
4-7-9-12CBS-Hytron, 100 Endicott St., Danvers, Mass. -2Cletron, Inc., 1974 E. 61 St., Cleveland 3, Ohio -9Columbia Records, 799 7 Ave., New York 9, N.Y.-8-11Components Corp., 106 Main St., Denville, N.J.-1-3-4-
7-8Concertapes, Inc., P.O. Box 88. Wilmette, 111.-8-10Cook Labs., Inc., 101 2 St., Stamford, Conn. -1-8-10Counterpoint Recordings Inc., 333 6 Ave., New York,
14, N.Y.-8-10Decca Records, 50 W. 57 St., New York 19, N.Y.-8DeRo Electronics, 134 Nassau Rd., Roosevelt, L.1.,
N.Y.-1-7-9DeWald Radio, Div., United Scientific Labs., 35-15 37
Ave., Long Island City 1, N.Y.-1-12Duotone Co., Locust St., Keyport, N.J.-2-5-6-7-9-10Dynaco Inc., 617 N. 41 St., Philadelphia 4, Pa. -1Dynamic Electronics -New York Inc., 73-39 Woodhaven
Blvd., Forest Hills, L.1., N.Y.-1-4-7-9-12Electron Enterprises, 6917 W. Stanley Ave., Berwyn,
111.-1-4-7-9Electronic Applications, 194 Richmond Hill Ave., Stam-
ford, Conn. -1-3-4-5-9-11Electronic Development Associates, 126 E. 46 St., New
York 17, N.Y.-1-4-12
For limitedbudgetstereo
Quam Hi-Fi Speakers performas well as or better Than hi -fl speakers
costino Jo to Twice as much
because their design emphasises
performance rather than
non-functional aecorative features.
Quam Hi-Fi Speakers offer you :he
See your (Doom distributoror write us directly forcomplete information on the fullline of Quam Hi-Fi Speakers-extended range, tweeters,woofers, coax iols.
QUAM-N1CHOLS CO.226 EAST MARQUETTE ROADCHICAGO 37, ILLINOIS
perfect way to keep within yourcustomer `s budget without
compromising the quality of The
system. Quam Hi-Fi Speakers
represent the accumulated
skill and experience ofthirty years of fine
speaker manufacturing.
Circle 91-01 on inquiry form p. 73
Ronette . . . world's most advanced stereo cartridgesRONETTE NEW STEREO CARTRIDGES exceed industry standards for monauraland stereo high fidelity. These superbly designed dual element cartridges . . .
both single stylus and turnover . . . are 00c; compatible with standard LP's,giving them new tonal brilliance. RONETTE STEREO CARTRIDGES offercleanest channel separation and high compliance so necessary for long recordlife and listening -pleasure with new stereo discs. Designed for hum -free per-formance in changer and transcription arms. RONETTE Transcription Arms areavailable with sierra cartridges.
BINOFLUID BF -40: Single dual-purposestylus .75 mil sapphire or diamond: 3 and 4terminal models available.
RONETTE STEREO CAR-TRIDGES have been ac-claimed "best by test" byindustry's leading editors andanalysts.
STEREO OV TURNOVER: 4Terminals: 2.5 and .75 mil sap-phire or diamond styli.
SPECIFICATIONS:Charmer Separation: 26-28 dbResponse: 20 to 15,000 cyclesConstruction: Parallel dual elements, four
pinsCompliance: 3.5 x 10-e cm/dyne vertical and
horizontalOptimum Stylus Pressure: 4-6 gramsStylus: Sapphire or Diamond
Write for FREE catalog of complete RONETTE One of cartridges, microphones and pick-uparms, for ltra.fldelity audio reproduction
ROtletie ACOUSTICAL CORPORATION, 190 Earl Avenue, Lynbrook, New York
Circle 91-02 on inquiry form p. 73
for Ultimate Fidelity
SHERWOOD!
+outstanding hon-ors bestowed, un-solicited, by mostrecognized testingorganizations.
No matter what your source of music-FM, your own discs, or tape-youwill enjoy it at its best coming fromSherwood's com plete home music center... most honored of them all ! Sherwoodtuners for example
First to achieve under one microvoltsensitivity for 20 db FM quieting in-creases station range to over 100 miles.Other important features include thenew "Feather -Ray" tuning eye, auto-matic frequency control, flywheel tun-ing output level control and cathode -follower output.
Model S-2000 FM -AM Tuner $139.50 net
Model S-3000 FM (only) Tuner $99.50 net
For complete specifications, write De t. ET -9
SHERWOODELECTRONIC LABORATORIES, INC.
2802 West Cullom Avenue, Chicago 18, Illinois
The "complete high fidelity home music center."
Electronic Instrument Co. (Eico), 3300 Northern Blvd.,Long Island City 1, N.Y.-1-9-12
Electro-Sonic Labs.. 35-54 36 St., Long Island City 6,N.Y.-2-3
Electro-Voice, Inc., Buchanan, Mich. -1-2-5-9Electrovox Co. (Walco), 60 Franklin St., East Orange,
N.J.-4-6-7Elektra Corp., 361 Bleecker St., New York 14,
N.Y.-8-10Emerson Radio & Phono. Corp., 14 & Coles Sts., Jersey
City 2, N.J.-7Ercona Corp., 16 W. 46 St., New York 36, N.Y.-1-2-
3-4-5-9-10-11-12Erie Resistor Corp., 644 W. 12 St., Erie 6, Pa. -1-2-12Fairchild Recording Equipment Corp., 10-40 45 Ave.,
Long Island City 1, N.Y.-1-2-3-7Fanon Electric Co.. 98 Berriman St., Brooklyn 8.
N.Y.-1-4-7Federal Electronics Sales, Federal Electronics Bldg..
Rockville Centre. L.I., N.Y.,-2Fen -Tone Corp., 106 5 Ave., New York 11, N.Y.-1-2-3-
4-5-6-7Ferrodynamics Corp., Gregg St. & Route 17, Lodi, N.J.-
(Sonoramic) -10Fidelitone Inc., 6415 Ravenswood Ave., Chicago 26,
111.-6-7-10-11Fidelity Distributors, 7803 Sunset Blvd., Hollywood 46,
Calif. -8-10Fourjay Industries, 2360 W. Dorothy Lane, Dayton 39,
Ohio -9General Electric Co., Specialty Electronic Components
Dept., W. Genesee St., Auburn, N.Y.-1-2-3-6-7-9General Kinetics Inc., 555 23 St., S., Arlington 2, Va.
-11Glaser -Steers Corp., 20 Main St., Belleville 9, N.J.-3Granco Products. Inc., 36-07 20 Ave., Long Island City
5, N.Y.-7-9-12Greene Co., L. Charlton, 314 Washington St., Newton
58, Mass. -1-7-9Hallmark Electronics Corp. (Paramount), 383 Concord
Ave., New York 54, N.Y.-7-8-9Harman-Kardon Inc., 520 Main St., Westbury, N.Y.-1-12Hartley Products Co., 521 E. 162 St., New York 51,
N.Y.-9Heath Co., Benton Harbor, Mich. -1-2-3-7-9-1210'1 Pacific Recording (Omegatape), 854 N. Vine St.,
Hollywood 38. Calif. -8-10Int'l Radio & Electronics Corp., S. 17 St. & Misha-
waka Rd., Elkhart, Ind. -11Jensen Industries, 7333 W. Harrison St., Forest Park,
111.-2-6Jensen Mfg. Co.. 6601 S. Laramie Ave., Chicago 38,
111.-9Klipsch & Associates, Hope, Ark. -9KLH Research & Devel. Corp., 30 Cross St., Cambridge,
Mass. -9Lafayette Radio, 165-08 Liberty Ave., Jamaica 33,
N.Y.-1-2-3-5-9-10-11-12Lansing Sound, Inc., James B., 3249 Casitas Ave., Los
Angeles 39, Calif. -9Leslie Creations, Lafayette Hill, Pa. -7Lipps Eng'g., Edwin A., 1511 Colorado Ave., Santa
Monica. Calif. -11Livingston Audio Products, P.O. Box 202, Caldwell,
N.J.-10London Records, 539 W. 25 St., New York 1, N.Y.-8Lowell Mfg. Co., 3030 Laclede Station Rd., St. Louis.
Mo.-9Luxo Lamp Corp.. 102 Columbus Ave., Tuckahoe, N.Y.-5McIntosh Lab. Inc., 2 Chambers St., Binghamton, N.Y.
1-12Magnavox Co., 2131 Butter Rd., Fort Wayne, Ind. -7Magnecessories, Box 6960, Washington 20, D.C.-11Magnecord Div.. Midwestern Instruments, P.O. Box 7186.
Tulsa. Okla. -11Marantz Co., 25-14 Broadway, Long Island City 6. N.Y.
-1Marco Industries, 3rd & Franklin Sts., Womelsdorf, Pa.
-11.Mercury Records Corp., 35 E. Wacker Dr., Chicago 1
111.-8Metzner Eng'g Corp., 1041 N. Sycamore Ave., Holly-
wood 38, Calif. -3-11Michigan Magnetics, Inc., Vermontville, Mich. -11Microtran Co., 145 E. Mineola Ave., Valley Stream.
N.Y.-7-11Miller Co., J. W., 5917 S. Main St., Los Angeles 3.
Calif. -12Miller Mfg. Co., M. A., 4 & Church St., Libertyville.
111.-2-4-6-7Minnesota Mining & Mfg. Co., 900 Bush Ave., St.
Paul 6, Minn. -10Mobil Electronics Mfg. Co., 1111 State Rd., 67 E.,
Anderson. Ind. -9-12Motorola, Inc., 4545 W. Augusta Blvd., Chicago 51, III.
-7Musicall Corp., 4512 W. Jefferson, Los Angeles 16,
Calif. -1-7National Tape Library, 2413 Penna. Ave., N.W., Wash-
ington 7, D.C.-10Neshaminy Electronic Corp., Neshaminy, Pa. -9Newcomb Audio Products Co., 6824 Lexington Ave.,
Hollywood 38. Calif. -1North American Philips Co., 230 Duffy Ave., Hicksville,
N.Y.-5-9-11Nortronics Co., 1015 S. 6 St., Minneapolis 4, Minn. -
1 -4-11Olympic Radio & Television, 34-01 28 Ave., Long
Island City 1. N.Y.-4-7-9ORRadio Industries, Inc (Irish), Shamrock Circle Ope-
lika, Ala. -10Oxford Components, Inc., 556 W. Monroe St., Chicago 6,
111.-9Pentron Corp., 777 S. Tripp Ave., Chicago 24, 111.-1-4-
9-11Permoffux Products Co., 4101 San Fernando Rd., Glen-
dale 4, Calif. -1-9-11Pfanstiehl Chemical Corp., 104 Lake View Ave., Wau-
kegan, 111.-6Philco Corp., "C" & Tioga Sts., Philadelphia 34, Pa. -7
Pickering & Co., Sunnyside Blvd., Plainview, L.I., N.Y.-2-3-4-6-9
Pilot Radio Corp., 37-06 36 St., Long Island City 1,N.Y.-1-4-7-9-12
Powers Co., J. J., 1317 S. 5 Ave., Maywood, 111.-1-4-9Precise Development Co., 2 Neil Court, Oceanside, N.Y.-
1-7-12Precision Electronics Inc. (Grommes), 9101 King St.,
Franklin Park, 111.-1-12Pro -Tex Reel Band, 2108 Payne Ave., Cleveland 14,
Ohio -11Quam-Nichols Co., 226 E. Marquette Rd., Chicago 37.
111.-9Bacon Electric Co., 1261 Broadway, New York 1, N.Y.-9Radio Corp. of America, Cherry Hill, Delaware Town-
ship. Camden 8. N.J.-7-11Radio Corp. of America. RCA Records Div., 155 E. 24
St.. New York, N.Y.-8Radio Eng'g Co.. Inquirer Bldg., Philadelphia 30. Pa. -3Radio Merchandise Sales, 2016 Bronxdale Ave., New
York 62, N.Y.-9Radio Music Corp., 84 S. Water St., Port Chester, N.Y.-
1-2-3Recoton Corp., 62-35 Barnett Ave., Long Island City 4,
N.Y.-2-6-7Reeves Soundcraft Corp., 10 E. 52 St., New York 22,
N.Y.-10Regency Div., Idea Inc., 7900 Pendleton Pike, Indiana-
polis 26, Ind. -1-12Reiter Co., F., 3340 Bonnie Hill Dr., Hollywood 28,
Calif. -11Rek-O-Kut Co., 38-19 108 St., Carona 68. N.Y.-3-4Revere Camera Co., 320 E. 21 St., Chicago 16, 111.-4Riemer Co., David, 601 W. 26 St., New York 1, N.Y.-
3-5-7-9Roberts Electronics, 1028 N. La Brea, Hollywood 38,
Calif. -1-4-11Robins Industries Corp., 36-27 Prince St., Flushing 54,
N.Y.-7-11Rockbar Corp., 650 Halstead Ave., Mamaroneck, N.Y.-
3-9Ronette Sales Corp., 190 Earle Ave., Lynbrook, N.Y.-2-3Sargent-Rayment Co., 4926 E. 12 St., Oakland 1, Calif.
1-12Saxton Products, Inc., 1661 Boone Ave., New York 60.
N.Y.-9-11Scott Inc., H. H., 111 Powder Mill Rd., Maynard,
Mass. -1-2-3-4-12Scott Instrument Labs., 17 E. 48 St., New York 17,
N.Y.-11Setchell-Carlson, Inc., New Brighton, St. Paul 12.
Sherwood Electronics Labs.. 4300 N. Calif. Ave.. Chi-cago 18. 111.-1-12
Shure Bros., 222 Hartrey Ave., Evanston, 111.-2-3-5-6-11Simpson Mfg. Co., Mark, 32-28 49 St., Long Island
City 3, N.Y.-1-12Smolin Labs., Woodbrook Dr., Springdale, Conn. -3-4-8-9
-10-11Sonotone Corp., Elmsford, N.Y.-2-5-9Stephens Trusonic Inc., 8538 Warner Dr., Culver City.
Stere-O-Craft, Div. Craft Recording Corp., 1650 Broad-way, New York, N.Y.-8-10
Stereophony Inc., 112 Oak Plaza. St. Paul 9, Minn. -10Stereo Sound Studios, 238 E. 26 St.. New York 10.
N.Y.-8-10Stevens Products, Inc., 86 Main St., East Orange, N.J.-7Stromberg-Carlson, Special Products Div., 1400 N.
Goodman St., Rochester 3, N.Y.-1-3-4-7-9-12Seperscope, Inc.. 8520 Tujunga Ave., Sun Valley. Calif.
-11Tandberg of America, 10 E. 52 St., New York 22, N.Y.
-9-10.11Tannoy (America) Ltd., P.O. Box 177, E. Norwich, L.1.,
N.Y.-1-2-5-9Tayloreel Corp., 185 Murray St., Rochester 6. N.Y.-11Tech Master Corp., 75 Front St., Brooklyn 1, N.Y.-1-4-
12Telectro Industries Corp., 35-16 37 St., Long Island
City 1, N.Y.-1-4-7-11Televex Co., 46 Lakeview Ave., Yonkers, N.Y.-2-6Thorens Co., Thorens Ave., New Hyde Park, N.Y.-3Turner Co., 909 17 St., N.E., Cedar Rapids, Iowa -5United Audio Products, 202 E. 19 St., New York 3,
N.Y.-2-3-7-9Universal Woodcrafters Inc., La Porte, Ind. -1-9University Loudspeakers, Inc., 80 S. Kensico Ave.,
White Plains. N.Y.-9Urania Records, 233 Main St., Belleville 9, N.J.-8-10Utah Radio & Electronic Corp., 1124 E. Franklin St.,
Huntington. Ind. -9Vanguard Recording Society, 256 W. 55 St., New York
19, N.Y.-8-10Vidaire Electronics Mfg. Corp.. 44 Church St., Baldwin.
L.I., N.Y.-7Video Instruments Co., 3002 Penna. Ave., Santa Monica,
Calif. -1-12Viking of Minneapolis, 9600 Aldrich Ave. S., Minnea-
polis 20, Minn. -4-11V -M Corp., Benton Harbor, Mich. -3-4-7-9Vox Productions, Inc., 236 W. 25 St., New York, N.Y.-
8-10Walsco Electronics Mfg. Co., 100 W. Green St., Rock-
ford, 111.-7-11Waters Conley Co., 17 E. Chestnut St., Chicago 11,
111.-7Weathers Industries, 66 E. Gloucester Pike, Barrington,
N.J.-1-2-3-4-9Webcor, Inc., 5610 W. Bloomingdale Ave., Chicago 39.
111.-1-3 -4-7-9-11Webster Electric Co., 1900 Clark St., Racine, Wis.-1-2-
4-5-6-9-11Wellcor, Inc., 1218 N. Wells St., Chicago 10. 111.-9Wells -Gardner & Co., 2701 N. Kildare Ave.. Chicago 39,
111.-1-4-7-9-12Wendell Plastic Fabrics Corp., 1220 Broadway, New
York 1, N.Y.-7Westinghouse Electric Corp., Metuchen, N.J.-7
Circle 92-01 on inquiry form p. 7392 ELECTRONIC TECHNICIAN Stereo, 1959
IN PROFIT
IN DEALS
IN ACCESSORY
PRODUCTS
IN GUARANTEES
IN MEW ITEMS
DUOTONE CO., INC.Ke)port, New Jersey
LJ Car'ada, Charles 1V. Pointon, Ltd.
Circle 93-01 on inquiry form p. 73
Start with the Best -To Hear the Best-, 111AIL IIE IID
FMANTENNAS
The FM artenna is themast important ink between
icur tuner anc the station.Poor signal capture cannotbe made up witiin the tuner
and amplifier. So startwith the best to hearthe bes: - install a
Taco FM antenna.There's a model for
every installationrequirement, and all
are available in easy -to -install kits with all
necessary transmissionwire and hardware. All
N models available ingold ancdized finish.
FREE! The FM antenna story - send for yourfree copy. The complete details on the whys andwherefores of FM antennas ..
TECHNICAL APPLIANCE CORPORATIONSHERBURNE, N Y.
Westminster Recordinb. Co., 257 7 Ave., New York 1,N .Y.-8-10
White Inc., Stan, 725 S. LaSalle St., Chicago 5, 111.-9Whitley Electronics, Inc., 411 S. Chauncey St., Colum-
bia City, Ind. -1-4-7-9-12Wollensak Optical Co., 20 E. 21 St., Chicago 16, 111.-11Zenith Radio Corp., 6001 W. Dickens Ave., Chicago 39,
111.-7Zodiac Recording Co., 501 Madison Ave., New York 22,
N.Y.-8-10
IndustryAssociations
with name of secretaryunless otherwise noted
Acoustical Society of America 335 E 45th St New York17 N Y Wallace Waterfall
American Institute of Electrical Engineers 33 W 39th StNew York 18 N Y N S Hibshman
American Institute of Physics 335 E 45th St New York17 N Y Wallace Waterfall
American Physical Society Pugin Physics Bldg ColumbiaUniversity New York 27 N Y Dr Karl K Darrow
American Standards Assn 70 E 45th St New York 17 N YGeorge F Hussey Jr
Association of Electronic Parts & Equipment Mfrs 11 SLaSalle St Chicago 3 III Kenneth C Prince
Audio Engineering Society P 0 Box 12 Old Cheisea StationNew York 11 NY CJ LeBel
Electronic Development Institute 125 E. 46 St NewYork 17 N Y B Berger
Electronic Industries Assn 1721 De Sales St N W Wash-ington 6 D C James D Secrest
Institute of High Fidelity Mfrs 125 E 23rd St New York10 N Y A. Schwartzman
Institute of Radio Engineers 1 E 79th St New York 21N Y George W Bailey
Instrument Society of America 313 Sixth Ave Pittsburgh22 Pa Wm H Kushnick Exec Director
Magnetic Recording Industry Assn 1555 N Bronson AveLos Angeles 28 Calif Edward A Altschuler ManagingDirector
National Appliance & Radio -TV Dealers Assn 1141 Mer-chandise Mart Chicago 54 Ill A W Bernsohn Exec VicePres
National Assn of Broadcasters 1771 N St N W Washington6 D C Everett R Revereomb
National Assn, of Electrical Distributors 290 Madison AveNew York 17 N Y Arthur W Hooper Exec Director
National Assn of Music Merchants 222 W Adams StChicago 6 III William R Gard
N ational Audio -Visual Assn Box 337 Fairfax Va RaySwank
National Electrical Mfrs Assn 155 E 44th St New York17 N Y Joseph F Miller Managing Director
N ational Electronic Distributors Assn 343 S Dearborn StChicago 4 III Gail Carter Exec Officer
Phonograph Mfrs Assn 37 W 53rd St New York 19 N YA D Adams
Purchasing Agents of the Radio -TV -Electronics Industry143-30 257th St Rosedale 22 N Y B J TrombollCorres Secy
Radio & TV Executive Society Biltmore Hotel New York17 N. Y Claude Barrere Exec Director
Record Industry Assn of America 1 E 57th St New York22 N Y John W Griffin
Representatives of Electronic Products Mfrs 600 S Michi-gan Ave Room 1219 Chicago 5 III R Edward Stemm
RETMA-See Electronic AssnSociety of Motion Picture & Tv Engineers 55 W 42nd St
New York 36 N Y Charles S StodterWest Coast Electronic Mfrs Assn 1435 S LaCienega Blvd
Los Angeles 35 Calif Cortlandt Van Rensselaer
"And we'll tell the neighbors that I
converted it to stereo!"Circle 93-02 on inquiry !arm p. 73 Circle 93-03 on inquiry form p. 73
ELECTRONIC TECHNICIAN Stereo, 1959
for
LOWESThum...noise...microphonicsin a high -p dual triode .
PfRE1,6..111 ,
G,'C 813'12 tlx 7-1
the
AmperexECC83 A PLUG-INREPLACEMENT FOR THE 12AX7
MICROPHONICS:
Negligible in amplifiers requiring aninput voltage of at least 50 my for anoutput of 5 watts. No specialprecautions against microphonicsnecessary even though the tube ismounted in the near vicinity of a loud-speaker with 5% acoustical efficiency.
HUM AND NOISE LEVEL:
Better than -60 db relative to 50 mywhen the grid circuit impedance is nogreater than 0.5 megohms (at 60 cps),the center tap of the heater isgrounded and the cathode resistor isby-passed by a capacitor ofat least 100 mfd.
OTHER Amperex TUBES FORHIGHFIDELITY AUDIO APPLICATIONS:
EL84/61385 9 -pin power pentode; 17 W PP6CA7/EL34 High -power pentode; 100 W PPEF86/6267 low -noise high -A pentodeECC81/12AT7 Low -noise medium -A dual triodeECC82/12AU7 Low -noise low -A dual triodeGZ34 Cathode -type rectifier; 250 ma.EZ80/6V4 9 -pin rectifier; cathode; 90 ma.EZ81/6CA4 9 -pin rectifier; cathode; 150 ma.
At All Leading ElectronicParis Distributors
(.11)
1.:1Amperex CILLE1
ELECTRONIC CORP..230 Duffy Ave., Hicksville, Long Island, N.Y.
93
Fromany Point of View,more Experts chooseACROSOUNDULTRA -LINEAR II
60 watt amplifier
DESIGN The combination of patentedULTRA -LINEAR circuitry-plus new HYBRIDFEEDBACK principle-VARIABLE DAMPINGcontrol, and ULTRA STABILITY, represents anew high in the art of amplifier design ... anexample of ACROSOUND'S latest achieve.ment in AMERICAN Know -How. This superiority of design now enables anyone with orwithout any previous knowledge of electronicsto assemble for himself or herself . (yesrit's that easy!) ... the finest of amplifiers andat a most reasonable cost. in only two hours!
PERFORMANCE By listening test, or by instruments ... second to none in clarity andfrequency response. Normal level distortion isvirtually unmeasurable-IM 1% or less at 60watts, 120 watts peak. Completely stable ...unaffected by loads, perfect square waves.
QUALITY Every part going into the assemblyof critical and even non -critical circuitry istested and checked to allow no more than*MA variation from ACROSOUND'S stand.ards. Specialized test equipment unavailablecommercially was designed in ACROSOUND'Slaboratories to achieve this result. Everyprinted circuit board is placed in trial opera-tion on a laboratory amplifier. Output tubesare matched by trial and double checked.
COMPONENTS ACRO'S newest TO -600 out-put transformer with special hybrid winding-separates functions of output circuit andfeedback circuit. Heavy duty, completelyassembled, and thoroughly tested, printedcircuit board assures uniformity of perform-ance. Low distortion EL34 output tubes areoperated well within their ratings ensuringlong tube life and optimum performance.PRICE In preassembled kit form so that youmay save money, learn while doing, and havethe proud satisfaction you built the best foronly $79.50 net ... or if you feel you wouldprefer it laboratory assembled it still repre.sents a bargain at $109.50 net.
HEAR IT AT YOUR DEALER NOW!
BE READY FOR ACROSOUND DISTORTIONLESSPRE- AMP DESIGNED FOR THE STEREO-PHILE
Experts know why ACRO is best!Others . . . Learn why! Write toACRO PRODUCTS
369 SHURS LANEPHILA. 28. PA.
Master Control
(Continued from page 50)need some attention when the loud-ness level is changed appreciably orwhen the seating arrangement isaltered. A possible solution andsimplification may be in the use ofa recently introduced dual volumecontrol which may be adjusted in-dividually and then operated jointlyby locking the concentric shafts.
A desirable characteristic of abalance control is to be able to bal-ance the output level of each of thetwo channels, one against the other,without altering the overall volumelevel. This can be accomplished bystacking two linear potentiometersand wiring one in reverse order asshown in Fig. 2. Adjusting this con-trol lowers the volume of one chan-nel and increases the volume of theother, thus keeping the total outputat the same level.
It is possible to use a compensatedtype of volume control as a combi-nation loudness contour and vol-ume level adjuster. Provisions maybe employed to switch the compen-sation network out, and leave thecontrol function to handle the vol-ume level only. Still another way isto use separate controls and net-works for each of these functions.
Functions & ModesThe most convenient way to
choose a program source is to beable to turn a switch to the desiredposition. A rotary -selector, multi -gang switch with up to 12 positionsmay be used for this purpose. Thecomplexity of the switch may beminimized by limiting its functionsonly to the job on hand. Furthersimplification can be achieved byusing the same input on the controlbox for more than one programsource. Consideration must be givento the impedance and amplification
Fig. 4-Speaker phasing switch provides aquick way to check for proper stereophasing while listening to a stereo program.
requirements of the program source.Where more than one source has thesame output characteristics, it canbe fed into the same jack on themaster control.
Fig. 3 shows a simple arrange-ment of two switches which can re-verse the two channels, or permitthem to play straight through. It isalso possible to select either channeland feed it into both amplifiers formonophonic listening on both am-plifiers and their respective speakersystems. This in effect doubles theamount of power output.
Other than the balance and vol-ume controls nothing thus far hasgone into the control box that wouldmaterially alter the requirements formatching impedances and other pre-amplifier functions. Manufacturersspecifications for matching andequalization should be followed. Ifthe amplifier and preamplifier do nothave the appropriate circuitry, itmay be built into the control box.Some manufacturers have inputadapters which can be plugged intothe line between the program sourceand the preamp.
In the absence of equalizationnetworks it is possible to set thebass and treble controls for properplayback, but the correct position ofthe controls will have to be prede-termined and marked.
With stereo via FM multiplexthere is a very nice feature: becauseof the sum and difference type ofprogram makeup, the output fromthe difference channel can be ad-justed and faded in. Without thedifference channel, both speakersystems get the same program; theyare virtually in parallel. As the dif-ference channel component isbrought up, the stereo effect ap-pears without abruptly changing theoutput from either speaker. Thismakes quite a sophisticated demon-stration.
This can also be done with otherstereo program source material, butit requires elaborate equipment toconvert the signal to sum and dif-ference components. Just one moreswitch, but not on the master con-trol, to consider. This is a speakerphasing arrangement for only onechannel as shown in Fig. 4. Since itis possible, for several differentreasons, to have stereo program ma-terial, at the output of each ampli-fier, in phase from one programsource and out of phase from an-other, and since the only valid wayto phase speaker systems for stereois by listening to the stereo pro-gram, a phasing switch is most con-venient. This switch can be locatedeither near the amplifier or thespeaker.
Circle 94-01 on inquiry form p. 7394 ELECTRONIC TECHNICIAN Stereo, 1959
Multiplexing
(Continued from page 63)
have the same information as therighthand microphone and the leftspeaker will have the same infor-mation that was impressed on theleft microphone.
(A+B) ( A -B) = 2A(A+B) - (A -B ) = 2B
The way the subcarrier is devel-oped is very interesting, and alsovery complex. The problems ofsignal-to-noise ratio, and cross talkare still occupying the full-timeefforts of many engineers. However,sufficient progress has been demon-strated to justify consideration bythe FCC for multiplex broadcasting.The subcarrier for FM multiplexingis nothing more than a continuoussinusoidal signal operating at a fre-quency of over 20,000 cycles. Thereason for selecting an ultrasonicfrequency is to prevent it frombeing heard and thus interferingwith the main program in a regularFM receiver not equipped for mul-tiplex. Also the receiver deemphasisnetwork does much to kill this highfrequency signal and keep it fromgetting into the audio amplifierstages. From 30be used in actual practice. Somework is now going on in approxi-mately the 32 kc to 67 kc range.
At the receiver end, the FM sta-tion is picked up and handled inthe conventional manner up to thepoint just past the second detectorand before the deemphasis net-work.
The A -+B portion is allowed togo straight through the receiver toboth amplifiers, while the A -B sig-nal is picked off by a bandpass filterbefore the deemphasis network hasan opportunity to attenuate it. Thissignal is then demodulated andpassed through a phase splitter. Thein -phase part of the A-B signal isfed to one amplifier and the out -of -phase part of the A -B signal isfed to the other amplifier. As wasshown, this action restores the rightand left signals.
Adapters are available for use inthose areas presently experiment-ing with FM multiplex for stereo.These units range in price from ap-proximately $50 to $100.
The FCC has already granted per-mission to some broadcasters to ex-periment with multiplexed stereo -casting on FM, and it looks asthough multiplexed stereo will beanother program source for stereoin the very near future.
TrueHigh-
FidelityI.44/
1
litOT
See your local radio -television service dealer.
OXFORDComponents, Inc. I
Subsidiary of Oxford Veen: Corp.
556 West Monroe StreetChicago 6, Illinois
Illustrated literatureavailable upon request._
OXFORD 3 -WAY SPEAKERSYSTEMS and
BASS REFLEX CABINETSEn -lance the beauty and comfort of your room while youen -lance the sound of your high fiderty. Every room willsparkle with these OXFORD cabinets whether for stereo orin a setting with ,just one cabinet. Here is double -dutydesign ... cabinets can be used for horizontal or verticalpositioning ... with use of tapered legs or runners whichare both supplied. Avail-able with or withoutOXFORD 3W20 3 -wayspeaker systems, to giveyou the best sound repro-duction..
Cabinet Mode/ No.
SR - I M Red MahoganyBR -IC CherryMIR 11/orde Oct
AudiophileNet
Complete 3 way speak., systemtor chow/ catnne/sMode/ 3W20 $ 30.00
.F.0.8. hattery
Circle 95-01 on inquiry form p. 73
When Converting Your "onoto .K'tereo...Use
MODELPAC -AMP- 1
See and hear it atyour Ioc& distributor
or Write fornearest source.
The ERIEAUDIO -AMPLIFIER KIT
featuring"PAC" and an ERIE
Printed Wiring Board
With these Plug-in Components:ERIE: "PAC" (Pre -Assembled Components)ERIE PRINTED BOARD TUBE SOCKETS
OUTPUT TRANS;ORMER CAPACITORS
FILTER CAPACITOR TONE CONTROL VOLUME CONTROL and SWITCH TUBES
S-FECIFICATIONS FOR ERIE STANDARD AUDIO -AMPLIFIER
Frequency Response. 30 cycles tc 12,000 cycles +0. -3.5 db. Sensitivity: 0.56 volt RMS (input at 1 KC) for 2 watt output. Power Output: 2 watts input Impedance: 2 megohms. Output Impedance: 4 ohms AC Power Consumption: 17 watts. Overall Dimensions: 6%" L x 45,6"W x37/5" H Shipping Weight: 2 lbs.
FLAc°}ieter4Z7?-46ERIE RESISTOR CORPORATION
ERIE PA
ELECTRONIC TECHNICIAN Stereo, 1959Circle 95-02 on inquiry form p. 73
95
ONLY.SONORAMICOFFERS HIGH
QUALITY TAPEIN A \\
PERMANENT'PLASTICCASE!
WIDE LATITUDE TAPE Protects against dirt. dust, mishandling. Easy to store. Exclusive index system. V -slot selection -finder reel. Tapes easily accessible.
Distortion free, lifetime lubrication to eliminatesqueal, adhesion, head deposits: Broad
plateau bias assures finest performance on all.recorders, high resistance to abrasion,
print -through, cupping.
For FREE lifetime time -tape ruler, write: T-111FERROOYNAMICS CORPORATION
LODI, NEW JERSEY
Circle 96-01 on inquiry form p. 73
Winegard FMAntennas Give YouMaximum ResultsFrom Your FM Tuner
The superior electricalcharacteristics ofWinegard FMantennas exact theultimate in hi-fisound reproductionfrom your FMequipment. Withouta doubt, these arethe finest FMantennas made...permanently goldanodized to give youyears of service.
Write for Freecomplete list of FMstations and folder onWinegard FM and TVantennas.
Model FM3ANon -directional,completely factorypre -assembled. Youcan install it yourselfin just minutes on anysurface. Includesantenna, mast,universal roof mount,fasteners, lead-inwire, set clip. $17.95.
Model FMY8A high gain8 -element directionalyogi. Flat frequencyresponse across entireFM band with 10.2db. gain. Ideal forfringe areas and longdistance reception.Users report receptionup to 200 miles. $22.95.
copyright 1958
Kinegard Co.3000 Scotten Boulevard Burlington, Iowa
Circle 96-02 on inquiry form p. 7396
Stereo Discs
(Continued from page 49)
cause the needle to go straight downif both channels are equally pullingin a downward direction. An out -of -phase force, that is, one channelpushing up and the other channelpulling down, will cause the needleto travel laterally to one side or theother depending upon the directionof the forces. Thus the stylus cantravel in any direction dependingupon the forces exerted on it. Fromthis it can be seen that even thoughthe information is cut into thegroove at a 45° angle, the stylus isdisplaced either horizontally or ver-tically or both from the referencegroove at any given moment. Etienif only one channel is modulated,there is a diagonal movement whichconsists of horizontal and verticalcomponents. The RIAA standardspecifies that lateral modulation ofthe stereo disc produce in -phasesignals to the speakers. This in -phase signal condition differs fromthe in -phase mechanical motion ofthe stylus and should not be con-fused.
One of the most difficult -to -understand phenomena of the single -groove stereo record is how thestylus can track a groove that seem-ingly has one sidewall going oneway, and another sidewall going an-other as shown in Fig. 5. Perhapsthis is due to difficulties engenderedby the inability to use old conceptsto explain new ones, and worse still,to at least temporarily discard anyprevious ideas. The first and prob-ably most important misconceptionto eliminate is that the weavingback and forth of the groove's side -walls indicate lateral motion. Thegroove in Fig. 4 has sidewalls goingback and forth in a Mae West fash-ion, yet there is no lateral motionon the part of the stylus. However,this pinching and expanding doesindicate a rising and falling stylus.It is the center of the groove thatdescribes lateral motion.
Since the stylus can assume a po-sition that is displaced both horizon-tally and vertically from a givenreference point, it is possible for thegroove to have different widths, anddifferent lateral displacement fromone instant to the next. Thereforethe groove walls do not appear to besymmetrical. The center line at pointA in Fig. 5 shows lateral movementto the left, and the wider distancebetween the walls shows verticalmodulation in a downward direction.At point B the stylus is riding high
but without any lateral displace-ment. Again there is no horizontaloffset at point C, but the stylus isway down. Point D indicates that thestylus is off to the right but ridingat reference height. If at this pointnot too much confusion has set in,it should be evident that it is possi-ble for a stylus to track such agroove.
This brings up a rather contro-versial point. Since the stylus con-tacts both sidewalls at any giveninstant, and since both its relativewidth and lateral displacementtransmits the intelligence to bothelements in the cartridge, is it cor-rect to say that one wall containsthe intelligence in one channel andthe other wall contains the otherchannel? Where would the needlebe if one wall were left out? Evenso, in the illustration in Fig. 5, theinner sidewall represents the leftchannel which in this case containsa higher frequency signal than theright channel, which in turn is re-sponsible for the shape of the outerwall. It is the combination of thetwo walls and their relative positionwhich provides the information tothe stereo or monophonic cartridge.Suffice it to say that it works, andit is revolutionizing the hi-fi in-dustry.
MICROPHONESCARTRIDGESTONE ARMSEARPHONESHARDWARE
Finest Quality Components
At Economy Prices
* Hi-Fi Components availablein various series
* Wide selection of electronichardware
* Rystl Cartridges featureMoisture Resistant elements
* Sold nationally . . for replacementor use in original equipment
FOR BIG SAVINGS USE RYSTL . . . Sendfor complete Rystl product and priceinformation
Rystl Distributorships still avail-able . . . inquiries about exclusivefranchises invited
DAVID RIEMER COMPANY, INC.601 West 26th Street, New York 1, N. Y.
Circle 96-03 on inquiry form p. 73ELECTRONIC TECHNICIAN Stereo, 1959
Needles for Stereo
(Continued from page 56)lateral components, which can pro-d ace corresponding distortions inboth "45" channels:
1. The 2nd harmonic of lateralcomponents appear in the verticalchannel. At high frequencies this isrelatively unimportant. But . . .
2. IM products (difference fre-quencies) from the lateral compo-nents also appear in the vertical.This can produce a buzzing sound on
gh-amplitude, complex high-fre-q lency sounds, such as those highimpact items.
3. Lower frequency componentsof vertical movement can intermodu-la te the higher frequency lateralcomponents, producing a "dithery"effect in the reproduction.
Stylus Size
There is still another effect due tothe vertical component of the re-cording. The size of the stylus cancause increased 2nd harmonic dis-tortion in the vertical componentp_us the production of difference fre-q lencies (IM) within these compo-nents, thus exaggerating #2 effectconsiderably. Fig. 3 shows how thepath traversed by a larger needled_ffers from the actual vertical com-ponent. Compare the shape of thedotted line with that of the actualcutting. The smaller the needle, themore nearly its path agrees with theoriginal recording.
The answer for this is a smallerstylus, which reduces both pinch ef-fect and its associated distortions,and the dominantly vertical distor-tion. Early experimental stereo rec-ords and styli for them have beenusing a tip radius of 0.7 mil, as com-pared with the standard 1 mil formonophonic LPs and 3 mils for the78s. The RIAA recommendation forthe future is 0.5 mil-and not with-out good reason, from what we haveseen!
But what does reducing tip sizedo? If the pickup design remainsabout the same, the effective compli-ance of the record vinyl at the stylustip will increase, so the resonant fre-quency will come down, unless themass of the stylus and its mountingcomes down proportionately. Thismeans it is more important than everto have a clean mounting.
Reducing tip size, and keeping thestylus pressure the same means thepressure per square inch (which al-ready measures in tons per squareinch) will be radically increased. A
ELECTRONIC TECHNICIAN Stereo, 1959
change from 1 mil to 0.5 mil willmultiply this wear -producing pres-sure by about 4 times.
Needle Material
Since the advent of LPs, the tran-sition from steel -to -sapphire -to -diamond has been gaining momen-tum. Now it is widely recognizedthat diamonds are not only the best,but by far the cheapest both for rec-ords and styli. The step to 0.5 milshould multiply this incentive to-ward the use of diamond needles.
Diamonds should be good: accu-rately shaped, precision mounted,and micropolished. Extra care isneeded when installing these newneedles. The life of a diamond cannot be taken for granted. It shouldbe checked regularly.
It is false economy to get a pickupwith one stylus and expect it to dodual service. Figs. 4 and 5 show what
NORMALPRESSURE
DISTORTEDSHAPE
OF GROOVE
ORIGINAL SHAPEOF GROOVE
GREATERPRESSURE
Fig. 5-Small stylus with normal pressurewill slide along the bottom of the aroove inan erratic manner. (B) Increased pressurereduces erratic behavior, but increases wear.
using a large stylus in a smallgroove, or vice versa, will do. Eitherway, if only the regular pressure isused, distortion is apt to result.Fig. 4A shows how a needle, whichis too large but with normal pres-sure, rides high in the groove. Dis-tortion due to a tendency to bounce,and in severe cases serious trackingproblems are introduced such asgroove skipping, and in the case ofchangers, failure to trip the cyclingmechanism. Distorted records andexcessive wear can be expected ifstylus pressure is increased, asshown in Fig. 4B. On the other hand,too small a stylus, with normal pres-sure, has a tendency to move aboutin the bottom of the groove in anerratic maner causing distortion andexcessive needle scratch, as shownin Fig. 5A. Increasing needle pres-sure in this case also results in dis-torted discs and excessive wear. In-creasing the pressure to avoid thisdistortion also results in consider-ably increased wear in the styli.
PRECISION ...
preciselyfor music!
A pickup preciselydesigned for music!
A stereo pickup withall the compliance,
frequency responseand distortion -free
performance requiredfor the highest quality
music reproduction.This...is the
STANTON Stereo-LU X VA LV E
where qualitystarts
and the musicbegins!
The STANTON Model 196UNIPOISE Arm with inte-grated Stereo- FLUXVAINEPickup-$59.85 with replace-able 0.7 mil diamondT -GUARD Stylus.
"Pile STANTON Model 371Stereo -FLUX VALVE Car-tridge - $29.85 with replace-able 0.7 mil diamondT -GUARD Stylus.
Hermetically sealed for a lifetime of trot,ble-free use. the STANTON Stereo -FLUX -VALVE performs in a way no other pickupcan equal. Use it in automatic or manualrecord playing systems.
PHOTOGRAPHED BY MORT WELDON
for those who con heat the bhfkreoce"
41,41111411 1,11.8 Froerrrr POODUCVS rPICKERING & COMPANY, INC.,
Plainview, N. Y.FLUXVALVE, T -GUARD, UNIPOISE are registered trademarks
Address Dept. M98 fora free copy ofIT TAKES TWO TO STEREO by Wallet 0. Stanton.
Circle 97-01 on inquiry form p. 7397
FAIRCHILD"sound of quality"
COMPONENTSideal for stereo conversionsideal complete stereo system
232 STEREO CARTRIDGE. . . finest record reproduction stereo
or monaural
282 STEREO ARM... perfect for 232 STEREO and
Fairchild monaural cartridges
412 SERIES TURNTABLES-1, 2 or 4 SPEED
engineered for stereo
248 STEREO PREAMP... full flexibility of control, unusually
accurate equalization
255A POWER AMPLIFIER... ideal second chanel amplifier, or for
both channels of a stereo systemfor complete details, write Dept. T-9
FAIRCHILDRECORDING EQUIPMENT CORP.
10-40 45th Avenue, Long Island City 1, N.Y.Circle 98-01 on inquiry form p. 73
SOUND -ORBITER List $9.952 -CHANNELConstant Impe.dance SpeakerControl.Master switchpermits opera-tion ofset speakers in-dependently ofall remoteloads.One crossover networkservices four sets of woof-ers and tweeters in anycombination. Constant im- Model HFS-4 (4 ohms)pedance maintained withdummy resistive loads. Model HFS-8 (8 ohms)Completely wired. Screwterminals for all connec- Model HFS-16 (16 ohms)tions. No soldering.
VELVETONE Crossover Network
For more informationsee your local partsdistributor or write
Extends high -frequency rangeof any amplifierand hi -ti system.Channels low fre-quencies to woof-er and high fre-quencies totweeter.Use on 4, 8 or18 ohm systems.
Model VT -2List $3.95
Dept. H134 NASSAU ROAD, ROOSEVELT, N.Y.
Circle 98-02 on inquiry form p. 73
Stereo Glossarybalance control: A differential gain
control, whose function is to in-crease the level in one channel,while reducing it in the other, orvice versa, without affecting theoverall volume level of the stereosystem.
binaural: Two eared; applied to akind of recording to be playedinto separate headphones to createa sense of depth which does notnecessarily reflect actual listeningconditions in the studio or con-cert hall.
cardioid: As applied to microphones,heart -shaped sensitivity pattern.Provides maximum pickup infront, and minimum pickup fromthe rear of the microphone.
compatibility: The ability of a newand old system to be used inter-changeably. Specifically, a stereosystem usable with monophonicprogram source; or stereo pro-gram that can be reproducedmonophonically on a monophonicsystem.
carrier: Unmodulated radio signalused to convey information throughspace.
compliance: Ability to yield or flex.In stylus and cartridge measure-ments it is expressed as an inte-gral number which is equal to thenumber of 10-6 cm moved by 1dyne of force. The higher thenumber the better.
counter: A type of FM demodulator,particularly suitable for a multi-plex subcarrier. It counts the num-ber of cycles and gives an outputproportional to its count at anyinstant.
decoding: In multiplex, a process ofseparating the subcarrier from themain carrier.
difference channel: A combinationof the difference between left andright stereo channels.
focus control: See balance control.forty-five/forty-five: The accepted
type of monogroove stereo record-ing, so named because the stylusmotion for each channel is at a45° angle.
hole -in -the -middle: An effect of adivided sound source sometimesencountered in an area midwaybetween speaker systems. An out -of -phase condition can exaggeratethis effect, as can too widely sep-arated speakers.
integrated: Applied to speakers orenclosure design, arrangement ofspeakers, usually on a commonaxis to create the impression thatthe sound is coming from a pointsource, especially the middle andhigh frequencies (in the samestereo channel).
matrixing: The proces of combiningleft and right channels, to producesum and difference signals. Alsothe reverse process, to restore leftand right channels from the sumand difference signals.
monaural: One eared. Frequentlyused loosely instead of monophonic.
monophonic: Single channel, whetherpresented over one or more speakersystems.
monogroove stereo disc: A stereorecording in which all the programis contained in one groove.
multiplex: A method of simulta-neously carrying one or more ad-ditional radio programs on oneradio transmission within the as-signed bandwidth.
omnidirectional: As applied to mi-crophones, uniform pickup ofsound from all directions.
ping-pong effect: Dissociation due tosome sounds coming first from onespeaker, and then from the other.
stereophonic: Also referred to asstereo. Two or more separatechannels of sound blended in alistening area in such a manneras to create a sense of realism anddepth in sound reproduction.
subcarrier: A relatively low ultra-sonic frequency used to acceptmodulation from additional pro-grams, such as a second stereochannel, and then modulating themain radio station carrier.
sum channel: A combination of leftand right stereo channels. It isidentical to the program whichmay be recorded or transmittedmonophonically.
vertical -lateral: A type of stereomonogroove recording in whichone channel is recorded by verti-cal movement and the other bylateral movement of the stylus;as a basic system, this has beenrejected in favor of 45/45.
98 ELECTRONIC TECHNICIAN Stereo, 1959
ears.loot.
'II ' inill o,,,
I. iltiiii14#41,A110fyiyis
A:......f/1/1////kim
WORLD -ACCLAIMED SHURE
Shure Dynetic moving magnet phonograph cartridgesand pick-up arms are designed to re-create sound withUTMOST accuracy-to satisfy the critical demands ofyour most exacting customers. And, they are made
STEREOfc ?re, CD,2\2\y/ti,-/-ze_
CARTRIDGE
Model M3D
Provides accuracy and honesty of sound.Is without equal in the re-creation of cleanlows, brilliant highs, and true -to -perform-ance mid -range. Fits 3- and 4 -lead ste-reo transcription -type and changer arms.Completely compatible, plays monauralor stereo. 10 -second stylus replacement.Frequency response: 20 to 15000 cpsOutput level: 5mv per channel at 1000cpsCompliance: 4.0 x 10-6cm per dyneChannel separation: More than 20 db
throughout the critical stereo frequencyrange.
Tracking force: 3 to 6 grams.Price: $45.00 audiophile net. Complete
with 0.7 mil diamond stereo stylus.
CARTRIDGES AND TONE ARMS
under custom laboratory conditions. Each unit ischecked electrically, mechanically and acoustically toinsure trouble -free performance that puts an end toprofitless service call-backs.
MONAURALPROFESSIONAL -.7/ir74/t7
CARTRIDGE
Model M5D
Fits record changer and transcription -typearms. Lowest needle talk, no hum pick-up,higher compliance . . . prolongs recordlife, needs no special transformer. Equalsor outperforms cartridges costing up to50% more! Easy stylus replacement with-out removing cartridge from arms.Frequency response: 20 to 20000 cpsOutput level: 21 my at 1000 cpsCompliance: 3 x 10-6cm per dyneTracking force: 3 to 6 gramsPrices: Model M5D-$27.50 net with
.001" diamond stylus (for LP records)Other Dynetic models $15.00 and up
MONAURALSTUDIO
TONE -ARM
.411.11t Model M16
"7reIONNEMMOMMIrmal.
tr.icks at 1 gram! Impossible to scratchrecords. With integral cartridge, .0007"diamond stylus. The ultimate in highfidelity- reproduces all the sound-evenbeyond the audible spectrum. Pays foritself in prolonged record life-tracks per-fectly at an incredible one -to -two grams.Even plays warped records with Hi-Firesponse. For transcription -type turnta-bles (M-12 for 12" records, M-16 for 16").Frequency response: 20 to 20000 cps
2 dbOutput level: 10 my at 1000 cpsCompliance: 7 x 10-6cm per dyneTracking force: 1 to 2 gramsPrice complete: $79.50 audiophile net.
Write for literature on monaural and stereo cartridges, tone arms, microphones, magnetic recording heads:Shure Brothers, Incorporated, 222 Hartrey Avenue, Evanston, Illinois, Dept. 14-I
Circle 99-01 on inquiry form page 73ELECTRONIC TECHNICIAN Stereo, 1959 99
Harman-Kardon stereo instruments are the most
flexible on the market today. Intelligent design assures
ease of operation. The new Duet stereo tuner and
Trio stereo amplifier - make stereo attractive,
effective, inexpensive - and sensible.
THE TRIO, Model A-224, StereoAmplifier - actually embodiesthree excellent instruments inone handsome, compact unit.The Trio is: A complete stereopreamplifier with two separate12 watt power amplifiers (24watt peaks each.) A complete24 watt monaural amplifier (48watt peak.) A 24 watt monaur-al amplifier with complete ster-eo preamplifier arranged toconvert an existing monauralamplifier to stereo. Outstandingfeatures include: Separateganged treble and bass controls,balance control, mode switch,speaker selector switch for localand remote speaker systems,contour control, tape outputfor recording application andrumble filter.
THE TRIO, Model A-224 $99.95the Cage (AC -24) optional 7.00
THE DUET, Model T-224,Stereo Tuner: Monaural! Bin-aural! Whatever the applica-tion, this new tuner is designedto give maximum performance.A superb monaural tuner-the1'-224 incorporates separate AMand FM channels for receivingstereo broadcasts through thisone unit. Rear jack makes itadaptable for multiplex recep-tion.While the DUET is an ideal AM/FM monaural tuner-it's specifi-cally designed for the growth instereo broadcasting. As stereobroadcasting grows - the valueof the DUET multiplies for you.Costs just a few dollars morethan conventional monauraltuners! (The DUET incorporatesa simple indexing scale to per-mit easy identification of fivepairs of "stereo" stations).
THE DUET, Model T-224$114.95
Prices slightly higher on the West Coast.
For additional information on Harman-Kardon stereo and monaural units, sim-ply send a postcard with the word stereoon it to Harman-Kardon, Dept. ET9,Westbury, N. Y.
harman kardon
Circle 100-01 on inquiry form page 73100 ELECTRONIC TECHNICIAN Stereo, 1959
