With this amplifier, you can obtain the best ofboth worlds. Technics' "New Class A" amolifiercircuit combines class A output with stable loadcondition on all stages. Also, the undistortedsound quality of class A and the efficient, high-output power of class B are available within asingle amplifier. You don't have to tradeefficiency and price for sound quality, orswitching distortion for high output.The SU-V6's facts and figures support theseclaims: 70 watts per channel, both channelsdriven into B ohms, trom 20 Hzto2O kHz with nomore than O.OO7% total harmonic distortion.The most important fact, though, is that this

integrated amplif ier's f aithf ully reproducedsound exhibits the effortless smoothness of trueclass A amplification. And yet all this is availableat a fraction of a conventional class A amolifier'scost.

New Glass A and Straight DCProvide Both Quality and QuantityQuality of reproduced sound and quantity ofoutput power are the two general aims we werestriving to develop in the advanced circuitryincorporated in the SU-V6.To test the success of our circuit designs,we have employed a new method of analysiscalled 3DA (first used in the development ofthe SU-8099 integrated amp), which stands for"3-Dimensional Analysis." With the aid of acomputer, this system enables us to testperformance at 4,000 points and express theresults in 3-dimensional graphic form. From ourextensive research using 3DA, we have foundthat performance requirements within the audiospectrum are best satisfied by building amplifiersthat exhibit good performance characteristics

Class B amplilier outputwavefom and distortionwavefom (at 20 kHz)

New class A amplif ier outpulwavefom and distortionwavefom (at 20 kHz)

Output Transistor Current Waveform

from 0 Hz (DC) at the bottom of the frequencyrange, all the way up to nearly 100 kHz in theultra-high range (it's undesirable to go muchhigher than this point, given currently availablecircuit components).To achieve oerformance within theseconsiderations, we have used a number ofadvanced circuit configurations, the two mostimportant of which are "New Class A" and"Straight DC."

New Class A with Synchro Bias forBetter High Frequency ResponseTransistor switching is a major cause of high-frequency distortion in class B and class ABamplifier designs. ln class B designs, two outpultransistors are used for each channel. The"upper" transistor handles the positive half ofthe waveform and the "lower" transistor handlesthe negative half. But problems occur when thesignal crosses the zero point; one transistor turnsoff and the other turns on. During this crossover,"switching distortion" is generated. This takesthe form of brief pulses with very sharp peaks,which produce high-order harmonic distortion.NFB (negative feedback) does not cope withswitching distortion effectively, despite itsusefulness in combating ordinary forms ofdistortion. This switching distortion can alsoresult in intermodulation distortion whichmuddies reproduced sound to a greater degree

than might be expected from a simple examina-tion of an oscilloscope trace. In class A, the sametransistor handles the entire waveform, but alarge idling current is required to operate thetransistor even when there is no audio inputsignal. Although this prevents any form ofswitching distortion, it also results in very lowefficiency. Large heat sinks must be provided todissipate the substantial amount of excess heatthat is created. Price is correspondingly high.In our New Class A circuihy, the output transistorbias current is synchronized with the positive andnegative swings of the.input signal so that theoutput transistors are always in an active state.With this remarkable circuitry, switchingdistortion is eliminated since the transistors arenever allowed to switch off. Because of thissynchronized operation, we call this "synchrobias." Besides preventing switching distortion inthe output waveform, it also presents linear loadconditions to the voltage amplification stage.Predriver load fluctuation is also minimized.The result is the virtual elimination of "crossoverdistortion."

"Straight DC" Configuration forDirect Coupling Between DC PowerAmp Section and High Level InputSignalsThe SU-V6's design takes full advantage of theexcellent low-range f requency response, phase-linearity, and low distortion inherent in ourrefined DC pourer amp design. By increasing thegain of the power amp section, we have made itpossible to directly couple high level inputs, suchas tuner, tape, and AUX sources, to the poweramp input. The resulting improvement in lowrange fidelity is a good example of what can beachieved with an innovative, yet uncomplicated,approach to integrated amp design. In fact, youcould view this configuration as simply a phonoequalizer and a DC power amp.While this characterizes the "simple is best"philosophy, some additional innovations werenecessary to obtain the desired performancegoals. First of all, a high-gain amp is required toraise typical "high level" inputs of 1 50 mV-200 mV to output levels of 70 W-100 W.Furthermore, any tendency toward temperaturedeoendent DC drift must be avoided since theamp's gain extends all the way down to DC in thelow range.To obtain high gain, Technics'SU-V6 ampemploys a linear cascode, 3-stage Darlingtonconfiguration which provides excellent open-loop performance. As a result, only 45 dB NFB isrequired to achieve the 0.007%fHD rating at70 Woutput.To combat DC drift, 1-chip dual FET's are usedfor the first stage differential amplifier. Since thisprevents mutual temperature differences, DCdrift is reduced to a mere + 1 0 mV from - 1 0'C to+50'c.

Concentrated Power Block (CPB)Prevents Distortion fromElectromagnetic InductionWith the strikingly clean high range responseobtained from our New Class A synchro biascircuitry, we made sure that nothing wouldinterfere with proper performance underpractical signal handling conditions.Our concentrated power block was developed toprevent electromagnetic induction betweenthose portions of the circuitry which handle largeamounts of current and those which handlesmaller signals. The power supply and outputstage were concentrated in one integrated unit to

create the shortest possible connections.With the addition of low impedance laminatedbus lines, the power supply loop was minimized.Another advantage of CPB is that it virtuallyeliminates significant dif ferences in performancebetween individual units. Consequently, you canexpect a maximumO.OOTo/o THD for anvindividual SU-V6 amp.

ICL Phono EQ Circuit EmplovinqUltra-Low Noise FETs Pei'miis

'

Direct MC Cartridge ConnectionThe first stage of the phono equalizer is adifferential amplifier with ultra-low noise dualFETs. As a result, no input capacitors arenecessary. A mere increase in equalizer gain,rather than an additional pre-preamp or step-uptransformer, is all that is needed for MC cartridgecompatibility. When the amp is in the straight D-Cmode, the only capacitor in the entire amp circuit,whether the input is MC or MM, is the EQ outputcapacitor.

Heavy Duty Power SuppliesIn an audio amplifier, the power supply must beable to meet the changes in impedancepresented by the speaker systems. Dependingon the frequency, this figure can range frombelow 4 ohms up to as high as 30 ohms for aspeaker system rated at 8 ohms.In the SU-V6, independent rectifier and ripplefilter circuits are provided for the left and rightchannels to assure truly stable DC power.Furthermore, the power transformer coils float ina special resin within shielded cases to preventpower supply hum.

Independent Recording Selectorwith 2-Way DubbingWith this versatile arrangement you can recordfrom one source while listening to another sincethe input and recording selectors are separate.Tape inputs are positioned on both the inputselector and the recording selector so that youcan record while listening to another source(such as a disc), if you wish.

Remote Action Switches EliminateExcess WiringRemote action switches are employed on theinput selector, recording selector, and phonoselector. Therefore, switching takes place at theideal location within the circuitry.This contributes to sound quality by minimizingthe chances of signal degradation due toextensive wiring.

Other FeaturesoHigh filter to cut out high frequency noise such

as record scratches and tape hiss.oFront-panel speaker selector lets you select

either of two pairs of speaker systems (A or B)or both at once (A+B).

aTone controls defeated at center oositionsetting.

Rear Panel Facilities8 9

1 0

PHONO inputsTUNER inputsAUX inputsTAPE DECK I Recording outputsTAPE DECK 1 Playback inputsTAPE DECK 2 Recording outputs

1 1

7. TAPE DECK 2 Playback inPuts8. Ground terminal9. Speaker terminals (main)

10. Speaker terminals (remote)'1 '1 . Voltage adjuster

ST-S7 and SU-V6

The ST-S7 Quartz Synthesizer FM/AM Stereo Tuner is iust the rightcompanion for your SU-V6. With the same clean, attractive styling andoutstanding performance standards, it perfectly complements the SU-V6Integrated DC Amplifier.

ffi (p'(p (b:: ,:Y 17

a .,r) $ xww n wq1 .2 .

A

5.6 .

20 Hz-20 kHz continuous power outputboth channels driven 80Wx2 (4())

70Wx2 (8cl)40 Hz-1 6 kHz continuous power output

both channels driven B0Wx2 (4O)70Wx2 (80)

1 kHz continuous power outputboth channels driven 90Wx2 (4O)

74Wx2 (8O)Total harmonic distortion

rated oowerat20 Hz-2O kHz

al 40 Hz-16 kqz

at 1 kHz

half powerat 20 Hz-2O kHzat 1 kHz

-26 dB power at 1 kHz5 0 m W p o w e r a t l k H z

Intermodulation distortionrated power

at 250 Hz:8 k{z=4:1 ,4Q O.O2%at60Hz:7 kHz:4:1, SMPTE, 8A 0.0O7%

Power bandwidth both channels driven, -3 dBTHD. 0.03%,5 Hz-60 kHz (4o)THD. O.O2%, 5 Hz-60 kHz (8O)

Residual hum & noise (Straight DC) 0.3 mVDamping factor 30 (4O), 60 (8O)

Headphones output level * ,tP"H3?,Uraaon

Load imoedanceMAIN or REMOTEMAIN and REMOTE

Input sensitivity & impedancePHONO MM

MCTUNER, AUXTAPE 1, REC/PLAYTAPE2

Phono maximum input voltageat 1 kHz. RMS. THD 0.01 %

MMMC

s/Nrated power4()

PHONO MMMC

TUNER, AUX-26 dB power 4ft

PHONO MMMC

TUNER, AUX50 mW power4O

PHONO MMMC

TUNER, AUX

Frequency responsePHONO RIAA standard curve +0.5 dB

(30 Hz-l5 kHz)TUNER. AUX. TAPE(Straight DC) DC-150 kHz (-3 dB)

+0, -0.3 dB (2O Hz-2O kHz)Tone controls

BASS 50 Hz, +10 dB- -10 dBTREBLE 20kHz, +10 d8- -10 d8

High-cut filter 7 kHz, -6 dBloctSubsonic f i l ter 20 Hz, -12 dB/octLoudness control

(volume at -30 dB) 50 Hz, +9 dBOutput voltage & impedance

o.o2% ga)0.007% (8o)0.o2% ga)

0.007% (8o)0.01% (4o)

0.007% (8o)

0.007% (8o)0.003% (8o)0.05% (4())0.08% (4o)

4()-16()8f)-16()

2 .5mV/47 kQ170 p.V/474

150 mV/36 ko170 mV/39 kO'150 mV/36 ko

150 mV1 0 m V

78 dB (86 dB, rHF A)68 dB (68 dB, rHF A,

250 pV input)92 dB (106 dB, IHF A)

150 mV30 mV/82 kO

+ 1 . 0 d B

55 dB

67 dB65 dB68 dB

64 dB62 dB65 dB

REC OUTREC/PLAY

Channel balanceAUX, 250 Hz-6300 Hz

Channel separationAUX,1 kHz

GENERALPower consumption 760 WPower supply AC 110/120/220/240V,

50/60 HzDimens ions (WxHxD) 430x153x351 mm

(1 6-1 5/1 6" x 6-1 /32" x 13-1 3/ 1 6")Weight 12.5 kg (27.6lb)

Note: Total harmonic distortion is measured bythe digital spectrum analyzel(HP 3045 system).

TechnicsMatsushita Electric

SD8OFOl OE2Spec i f i ca t ions sub jec t to change w i thout no t ice . Pr in ted in Japan.