THE PIANO KEYBOARD INSTRUMENTS The Science of Sound, Chapter 14
The Physics of Musical Instruments, Chapters 11, 12, 17 The Science
of String Instruments, Chapter 20
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GRAND PIANO
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PIANO BARTOLOMEO CRISTOFORI (1709): Gravicembolo col piano et
forte GOTTFRIED SILBERMANN JOHANNES ZUMPE ANDREAS STEIN Invented
escape mechanism PIERRE ERARD Invented agraffe, double repetition
action JOHN HAWKINS, ROBERT WORNUM Upright pianoforte 243 Strings
(5cm to 2m in length) on typical concert grand 8 Single strings
(wrapped) 5 Pairs of strings (wrapped) 7 sets of 3 strings
(wrapped) 68 sets of 3 strings (unwrapped) Strings tensions may
exceed 1000 N (215 lb.) (Total force: over 20 tons)
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SIMPLIFIED DIAGRAM OF PIANO WHEN A KEY IS DEPRESSED, THE DAMPER
IS RAISED AND THE HAMMER IS THROWN AGAINST THE STRING VIBRATIONS OF
THE STRING ARE TRANSMITTED TO THE SOUNDBOARD BY THE BRIDGE
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GRAND PIANO ACTION
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UPRIGHT PIANO ACTIONS FULL SIZE CONSOLESPINET
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(a) SINGLY-WOUND STRING AND (b) DOUBLY-WOUND STRING
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DEVIATION FROM EQUAL TEMPERAMENT IN A SMALL PIANO
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HAMMER VOICING
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SOUND SPECTRA FOR C 4 ON GRAND PIANO
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VIBRATIONAL MODES OF AN UPRIGHT PIANO SOUNDBOARD VIBRATIONAL
FREQUENCIES OF PIANO SOUNDBOARD COMPARED TO PLATE WITH SUPPORTED
AND FIXED EDGES
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MODE SHAPES GRAND PIANO SOUNDBOARDS
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DECAY TIMES FOR A SINGLE D 4 # STRING
Slide 14
COMPOUND DECAY IN A TRICORD WHEN A HAMMER STRIKES A TRICORD (3
unison strings), IT SETS ALL THREE STRINGS INTO VIBRATION WITH THE
SAME PHASE. BECAUSE OF SMALL DIFFERENCES IN FREQUENCY, HOWEVER,
THEY SOON GET OUT OF PHASE, AND THE RESULTANT FORCE ON THE BRIDGE
IS DIMINISHED. INITIALLY THE DECAY IS RAPID AND THE SOUND IS LOUD;
THEN THE DECAY RATE DIMINISHES, AND THE SOFTER SOUND CONTINUES FOR
AN EXTENDED TIME. IN THIS WAY THE PIANO PLAYS BOTH LOUD AND SOFT
(FORTE-PIANO)
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DECAY TIMES FOR DIFFERENT PARTIALS IN FIVE NOTES ON A GRAND
PIANO (Meyer 1978)
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RADIATION PATTERN (VERTICAL PLANE)
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HARPSICHORDS AND CLAVICHORDS SCIENCE OF SOUND, Chapter 14
PHYSICS OF MUSICAL INSTRUMENTS, Chapter 11 ANALYSIS OF THE DESIGN
AND PERFORMANCE OF HARPSICHORDS (N.H.FLETCHER, ACUSTICA 37, 139
(1977).
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MODERN FLEMISH HARPSICHORD BY AUSTRALIAN CAREY BEEBE BASED ON
CLASSICAL INSTRUMENTS BY THE 17 TH CENTURY MAKER ANDREAS RUCKERS.
THE KEYBOARD COMPASS HAS BEEN EXTENDED DOWN TO G3 IN THE BASS AND
UP TO D6 IN THE TREBLE THE SMALL PROTRUSIONS ON THE RIGHT SIDE
(CHEEK) ENABLE THE PLAYER TO ENGAGE EITHER OF THE TWO SETS OF JACKS
BY SLIDING THE REGISTER ON OR OFF
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HARPSICHORD ACTION (SIMPLIFIED)
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HARPSICHORD ACTION ACTION OF A FLEMISH HARPSICHORD. IN THIS
INSTRUMENT THERE ARE TWO CHOIRS OF STRINGS, THE SHORTER 4-FT CHOIR
AND AN 8-FT CHOIR. THE LEATHER PADS OF THE BUFF STOP ARE VISIBLE
BEHIND THE 4-FT TUNING PINS
Slide 21
CLAVICHORD THE CLAVICHORD, LIKE THE PIANO, DEPENDS ON STRUCK
STRINGS FOR ITS SOUND. A CLAVICHORD IS A PORTABLE INSTRUMENT WITH A
SOFT DELICATE SOUND CLAVICHORD ACTION: A TANGENT STRIKES THE STRONG
(OR PAIR OF STRINGS) AND CAUSES THE PORTION BETWEEN THE TANGENT AND
THE BRIDGE TO VIBRATE
Slide 22
CLAVICHORD SOUND UNLIKE THE HARPSICHORD, THE CLAVICHORD PLAYER
HAS DIRECT DYNAMIC CONTROL OVER THE SOUND BY VARYING THE SPEED AT
WHICH THE TANGENT STRIKES THE STRING AND THE FORCE WHILE THE SOUND
IS SUSTAINED. THE FORCE ON THE BRIDGE HAS A SPECTRUM THAT FALLS
SMOOTHLY AT ABOUT 8 dB/OCTAVE. BECAUSE THE DISPLACEMENT OF THE
STRING BY THE TANGENT INCREASES ITS TENSION BY A SMALL AMOUNT, THE
PLAYER CAN CREATE A PITCH VIBRATO BY VARYING THE FINGER FORCE ON
THE KEY. THE FACT THAT EACH NOTE IS PRODUCED BY TWO STRINGS
PRODUCES AN EFFECT SIMILAR TO THAT FOUND IN PIANOS. IMMEDIATELY
AFTER STRIKING, THE STRINGS VIBRATE IN PHASE, AND VIBRATIONAL
ENERGY IS TRANSFERRED RAPIDLY TO THE BRIDGE AND SOUNDBOARD, LEADING
TO A RAPID INITIAL SOUND DECAY WITH AN AFTERSOUND AFTER THE TWO
STRINGS GET OUT OF PHASE. THIS LEADS TO AN INITIAL CLARITY OF SOUND
COMBINED WITH A MELLOWNESS.
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HARPS
Slide 24
CONCERT HARP
Slide 25
MODERN CONCERT HARP THE MODERN CONCERT HARP HAS 46 or 47
STRINGS RUNNING from C1 or D1 to G7. THE STRINGS RUN FROM THE
CENTER OF THE SOUNDBOARD TO THE LEFT SIDE OF THE NECK. AT THE TOP
THEY ARE WRAPPED AROUND A TUNING PEG, USED FOR TUNING, AND A BRIDGE
PIN. BENEATH THE BRIDGE PIN ARE THE TUNING DISCS WHICH RAISE THE
PITCH ONE OR TWO SEMITONES. THE STRINGS ARE TUNED A SEMITONE FLAT;
THE FIRST DISC RAISES THE STRING TO NATURAL; THE SECOND TO SHARP.
THE SHARPING MECHANISMS ARE CONTROLLED FROM 7 PEDALS. THE MECHANISM
IS QUITE COMPLEX AND RUNS UP THE FOREPILLAR OR POST INTO THE
NECK.
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PLAYING SHARPS AND FLATS DEPRESSING ONE OF THE TUNING PEDALS
INCREASES THE TENSION ON ALL THE STRINGS WITH THAT NOTE NAME BY ONE
(FOR NATURALS) OR TWO (FOR SHARPS) UNITS
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PIPE ORGAN THE PIPE ORGAN HAS BEEN CALLED THE KING OF MUSICAL
INSTRUMENTS. NO TWO PIPE ORGANS IN THE WORLD ARE EXACTLY ALIKE A
LARGE VARIETY OF PIPES ARE ARRANGED INTO DIVISIONS EACH DIVISION IS
CONTROLLED BY A SEPARATE KEYBOARD OR MANUAL, INCLUDING THE
PEDALBOARD PLAYED WITH THE FEET SWELL ORGAN: USUALLY ENCLOSED
BEHIND SHUTTERS GREAT ORGAN: PRINCIPAL DIVISION WITH MANY STOPS
POSITIVE ORGAN: INCLUDES SOLO STOPS PEDAL ORGAN: INCLUDES THE
LOWEST BASS STOPS
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ORGAN WINDCHESTS HAVE VALVES THAT CAN BE OPENED TO ADMIT AIR
INTO THE PIPES THE OLDEST TYPE IS THE TRACKER OR MECHANICAL ACTION:
KEYBOARDS ARE CONNECTED DIRECTLYTO THE WINDCHESTS DIRECT ELECTRIC:
ELECTROMAGNETS OPEN VALVES ELECTROPNEUMATIC: ELECTROMAGNETS EXHAUST
AIR FROM THE BELLOWS, WHICH OPEN THE VALVES INTO THE PIPES FULL
PNEUMATIC: (RARE THESE DAYS) KEY CONTROLS AIR VALVE TRACKER DIRECT
ELECTRIC ELECTROPNEUMATIC
Slide 29
SCHLIEREN PHOTOGRAPHS SHOWING AIRFLOW WHEN A JET STRIKES A
SHARP EDGE (A. Hirschberg) FLUE PIPE: A JET OF AIR STRIKES A SHARP
EDGE AND ALTERNATELY FLOWS INTO AND OUT FROM THE PIPE (AS IN A
RECORDER) AS DRIVEN BY POSITIVE FEEDBACK FROM THE PIPE
Slide 30
ORGAN PIPES ARE ORGANIZED INTO RANKS OF SIMILAR PIPES ONE RANK
WILL INCLUDE ONE PIPE FOR EACH NOTE (EXCEPT FOR MIXTURE STOPS) FLUE
(LABIAL) PIPES PRODUCE SOUND BY A VIBRATING JET, LIKE A FLUTE REED
(LINGUAL) PIPES HAVE A VIBRATING REED, LIKE A CLARINET OPEN FLUE
PIPE (metal) STOPPED PIPE (wood) REED PIPE
Slide 31
IN AN ORGAN REED PIPE, A METAL REED VIBRATES AGAINST A SHALLOT,
MUCH AS A CLARINET REED VIBRATES AGAINST THE LAY OF A MOUTHPIECE.
PRESSURE (POSITIVE) FEEDBACK LOCKS THE REED VIBRATIONS TO A
RESONANCE OF THE PIPE THE VIBRATING REED ISTUNED BY MEANS OF A
TUNING WIRE TO A FREQUENCY NEAR THAT OF ONE OF THE PIPE RESONANCES.
REED PIPES, WHICH HAVE CYLINDRICAL OR CONICAL RESONATORS, ARE GIVEN
SUCH NAMES AS CLARINET, KRUMMHORN, TROMPETTE, RANKETTE, etc.
Slide 32
RESONANCE FREQUENCIES OF OPEN AND CLOSED PIPES, CYLINDRICAL AND
CONICAL
Slide 33
COUPLING OF REED TO RESONATOR THE REED CAN COUPLE TO ANY OF THE
PIPE RESONANCES A G4 TROMPETTE PIPE HAS RESONANCES AT 243, 488,
729, AND 972 Hz, SHOWN BY THE HORIZONTAL LINES. BY VARYING THE
VIBRATING LENGTH OF THE REED, IT CAN BE MADE TO LOCK INTO ANY OF
THESE RESONANCES. (Mikl s, Angster, Pitsch, and Rossing, 2006)
Slide 34
PIPE RESONATORS MAY BE OPEN OR CLOSED CYLINDERS, CONES. BROAD
FLUTE PIPES EMPHASIZE THE FUNDAMENTAL, WHILE STRING STOPS HAVE
NARROW PIPES WITH MORE HARMONICS. DIAPASON OR PRINCIPAL STOPS ARE
SOMEWHERE BETWEEN.
Slide 35
PIPE SCALING THE SCALE OF A RANK OF PIPES REFERES TO THE RATIO
OF DIAMETER TO LENGTH FOR THE PIPE OF LOWEST PITCH FOR AN OPEN
CYLINDRICAL PIPE, THE END CORRECTION AT THE OPEN END ADDS 0.6 TIMES
THE RADIUS, WHEREAS AT THE MOUTH OF A FLUE PIPE, ONE ADDS ABOUT 2.7
TIMES THE RADIUS THUS IN A LARGE-SCALE PIPE, ONLY THE LOWEST
HARMONICS ARE SOUNDED NORMALLY, THE MOUTH WIDTH, LIP CUT-UP, AD
WIDTH OF THE FLUE OPENING FOLLOW THE SAME SCALE AS THE PIPE
DIAMETER
Slide 36
SOUND RADIATION FROM FLUE PIPES A STOPPED PIPE RADIATES ONLY
FROM ITS MOUTH; THE RADIATION OF THE FUNDAMENTAL AND LOW HARMONICS
IS NEARLY ISOTROPIC. FOR HIGHER HARMONICS THE RADIATION IS MORE
CONCENTRATED IN FRONT OF THE MOUTH AN OPEN PIPE HAS TWO COHERENT
SOURCES AT THE MOUTH AND OPEN END, WHICH ARE IN PHASE FOR ODD
HARMONICS AND OUT OF PHASE FOR EVEN HARMONICS. TYPICAL RADIATION
PATTERNS ARE:
Slide 37
THE PIPES OF AN ORGAN CAN BE LAID OUT IN A MATRIX. EACH ROW
CONTAINS PIPES OF A SINGLE RANK EACH COLUMN CONTAINS ALL PIPES FOR
A SINGLE NOTE. DRAWSTOPS CONTROL ADMISSION OF AIR TO THE PIPES OF A
RANK KEYS CONTROL AIR TO PIPES OF A NOTE PIPES AT ALL ACTIVE
INTERSECTIONS PRODUCE SOUND
Slide 38
ORGANS IN STANFORD MEMORIAL CHURCH MEMORIAL CHURCH HAS FOUR
ORGANS: THE MURRAY HARRIS ORGAN WAS BUILT IN 1901 AND ENLARGED IN
1915. THE FISK-NANNEY ORGAN, BUILT IN 1985, IS THE LARGEST, WITH 73
RANKS AND ALMOST 4500 PIPES THE SIDE CHAPEL HOUSES THE KATHERINE
POTTER-BRINEGAR ORGAN, A ONE-MANUAL RENAISSANCE-STYLE ORGAN BUILT
IN 1985 THE CONTINUO ORGAN WITH THREE STOPS, BUILT BY MARTIN PASI,
WAS ACQUIRED IN 2001
Slide 39
WANAMAKER ORGAN (PHILADELPHIA) Built by the Los Angeles Art
Organ Company for the 1904 St. Louis World's Fair, the Wanamaker
Organ was designed by renowned organ architect George Ashdown
Audsley.. This heroic instrument had more than 10,000 pipes, and
its construction was on such a lavish scale that costs soared to
$105,000, bankrupting the builder.
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CONVENTION HALL (ATLANTIC CITY) THE WORLDS LARGEST ORGAN, WITH
30,000 PIPES, IS IN THE ATLANTIC CITY CONVENTION HALL
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TUNING ORGAN PIPES REED PIPES ARE TUNED BY MOVING THE TUNING
WIRE UP AND DOWN. FLUE PIPES ARE TUNED BY CHANGING THE EFFECTIVE
LENGTH. IN A CLOSED PIPE, THIS IS ACCOMPLISHED BY MOVING THE
STOPPER UP OR DOWN. MANY OPEN PIPES HAVE A TUNING SLEEVE THAT
SLIDES UP AND DOWN; OTHERS HAVE AN ADJUSTABLE SLOT NEAR THE OPEN
END.
Slide 42
VOICING ORGAN PIPES VOICING MEANS MAKING ADJUSTMENTS IN THE
VARIOUS PARTS OF THE PIPE SO THAT IT SPEAKS PROPERLY. SOME OF THE
MAIN PARAMETERS ADJUSTED DURING VOICING: THE SIZE OF THE FOOT BORE
THE CONDITION OF THE BORE NICKING THE WIDTH OF THE FLUE OBSTRUCTION
NEAR THE MOUTH (ROLLER BEARD) THE HEIGHT OF THE LANGUID THE HEIGHT
OF THE MOUTH (CUT-UP) SETTING OF THE UPPER LIP THE CONDITION OF THE
UPPER LIP