THE
JOURNAL
OF
ACOUSTICAL
THE
SOCIETY
Volume
32
OF
Number
MARCH
AMERICA
3
ß 1960
Electronic Music Synthesis
H. F. OLSON,H. BELAR,ANDJ. TI•ENS*
RCA Laboratories,
Princeton,New Jersey
(ReceivedDecember9, 1959)
Themodern
systems
ofcommunication
havebeenapplied
to theelectronic
synthesis
of musicin theform
of theelectronic
musicsynthesizer.
Theelectronic
musicsynthesizer
is a machine
whichprovides
means
forproducing
a tonewithanyfrequency,
intensity,
growth,
duration,
decay,
portamento,
timbre,vibrato,
anddeviations.
If theseproperties
ofa tonearespecified,
thetonecanbeproduced
by thesynthesizer
from
a codedrecord.For implementing
the electronic
synthesis
of musican improved
andenlarged
electronic
musicsynthesizer
Mark II hasbeendeveloped
andbuilt.Thenewelectronic
musicsynthesizer
andtheuse
of the new synthesizer
by professional
musicians
will be described.
INTRODUCTION
ing,soundmotionpictures,andtelevisionuponthe dis-
seminationof information, art,
HEREaretwomaincategories
ofcommunicating
information in the form of sound waves in which
and culture has been
tremendous.The reproductionof sound in these fields
mentofknowledge
the ear is the ultimateusefuldestination,namely,the hasbeenasimportantto theadvance
as the printingpressand the printed page.
The new systemsof communication
involvingthe
originalspeechor musichasbeenextendedby the reprocesses
of
analysis,
encoding,
coding,
decoding,
and
productionof sound.The reproductionof soundis the
are beginningto play an importantpart
process
of pickingup soundin onelocationand repro- synthesizing
information
in all forms.In thispaper
ducingat the samelocationor someotherlocationeither in communicating
will be that of the application
at the sametime or somesubsequent
time. The most the main consideration
to the
commonsoundreproducingsystemsare the telephone, of new elementsand systemsof communication
phonograph,
radio,soundmotionpicture,andtelevision. production of music.
The radio, phonograph,soundmotion picture, and
PRODUCTION
OF MUSIC
televisionhavemadeit possible
for all thepeopleof the
Musicisbothanart anda science.
In scientific
terms,
world to hear famousstatesmen,artists, actors,and
musicis the art of producingpleasing,expressive,
or
musical aggregationswhere only a relatively small
intelligible
combinations
of
tones.
The
sounds
of
original
number had been able to hear them first hand. It is
musicareproduced
by thehumanvoiceor by an instruevidentthat the reproductionof soundhasproducedin
ment actuated by a musician.Most music is recorded
a relativelyshort time a great changein the education
andtranslatedinto sounds
by meansof a symbolicnoand entertainment of this and other countries. The
tation on paper.The ultimateobjectivedestinationof
impactof the telephone,phonograph,
radiobroadcastall musicalsounds
is thehumanear.Thus,theproducof the followingprocesses:
the
* Associated
with the RCA Laboratoriesduringthe electronic tion of musicconsists
synthesisof musicdescribedin this paper.
symbolicnotationuponpaperby the composer,
the
human voice and music. The direct transmission of the
311
Copyright•) 1960 by the AcousticalSocietyof America.
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312
OLSON,
j OO
IOOOO
1,50
FREOUENCY
(PITCH)
:50 IJO
BELAR,
!
IOOO
FREQUENCYIN CYCLES PER SECOND
TIMMENS
translationof thesymbolic
notationintomusicalsounds
by the musician
employing
eitherhis ownvoiceor a
musicalinstrumentor both, and the actuationof the
humanhearingmechanism
by themusicalsounds.
The
120
•-•
medium of transmissionfrom the musician and musical
instrument to the listener is sound waves. These sound
øIm
INTENSITY
AND
wavescarry the musicaltones.The propertiesof a
(LOUDNESS)
musical tone will be described in the section which
follows.
F
GROWTH
STEADY
STATE
DuRATIO
N
•/
PROPERTIES
STEADY
STATE
OF A TONE AND ELECTRONIC
SYNTHESIS
OF MUSIC
DECAY
The propertiesof a musicaltone are frequency
(pitch),intensity(loudness),
growth,duration,decay,
DURATION
TIME
IN
SECONDS
z
•
portamento
(frequency
glide),timbre(waveform),
and
•
vibrato. There are in addition,in someinstances,vari-
PORTAM
ENTO •
ous deviations in these characteristics. These characTIME
IN sECONDS
teristicsof a tone are depictedin graphicalform in
Fig.1. Thedefinition
andrelation
of thesetermsto the
electronicsynthesis
of musichave beenoutlinedin
TIMBRE
, I !,,,
Ioo
Jooo
•obdo
FREQUENCY IN CYCLES PER SECOND
VUVVVV
AMPLIT UDE
FR EQUE NCY
MODULATION
MODULATION
Fro. 1. The characteristics of a tone.
detail in a previouspublication)
An electronicmusicsynthesizer
was developedand
builtbased
upontheproduction
oftonesin termsof the
fundamental
properties
of a tone as outlinedabove.
The electronic
musicsynthesizer
hasbeendescribed
in
detail in reference1. In this connection,an improved
modelof the electronicmusicsynthesizertermedthe
Mark II hasbeendeveloped
andbuilt. It is the purpose
RECORD
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PAPER
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RECORD
L
OTO.
R
TURNTABLE
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)u
tASTER
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,I'
MOTOR
•
•,,
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CU•TER
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RECORD
Fro.2. Schematic
blockdiagram
of theelectronic
musicsynthesizer
Mark II.
xH. F. OlsonandH. Belar,J. Acoust.
Soc.Am.27, 595-612(1955).
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TURNTABLE
ELECTRONIC
MUSIC
SYNTHESIS
313
o
5
7
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tl
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.:.•
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:
:::::::::::::::::::::::::::::,-,,
..':'?:::: .::•::..:'"
::•
::•,.
Fro. 4. Binary conversionsystemconsistingof the paper drum,
paper record,brushes,and relay tree.
•.:.•
::::':::::•:'
:::::::::::::::::::::::::::::::::::
.:•:::::G:•
....
========================:.."•.•:•:::::::::..F•.••...:.•:.:•:.:.::::.::.:::.:•.:::::•:
Fro. 3. Electronic music synthesizerMark II.
of the section which follows to describe electronic music
synthesizer
lX{arkII.
ELECTRONIC
MUSIC
SYNTHESIZER
MARK
II
consistof twelvefixedfrequency,tuningfork controlled,
vacuumtube oscillatorstuned to the frequenciesin one
octave of the equally tempered scale and associated
¾ARIABL[
FREQUENCY
VARIABLE
FREOUENC¾
FIXES
FREOUENC¾
OSCILLATORS
OSCILLATORS
OSCILLATORS
SET 2
MULTIPLIERS
SET I
A schematicblockdiagramof the completeelectronic
musicsynthesizer
l•lark II with meansfor producing
all the characteristicsof a musical tone, as outlined in
the precedingsectionand depictedin Fig. 1, is shown
in Fig. 2. Photographs
of the electronic
musicsynthesizerMark II areshownin Figs.3 (a) and (b). Referring
to Fig. 2, it will be seenthat thereare four complete
channels,two paper records,and two recordingturntables.Employingfour completechannels
makesit possible to record four series of tones at one time. The two
paper recordsand the two recordingturntablesare
electricallyand mechanically
interlockedthroughthe
motorsandgenerator
drivenfroma mastermotorwhich
insuresabsolutesynchronism
betweenthe paperrecords
and the recordingturntables.
In order to simplify the operationof the electronic
musicsynthesizer
and reducethe numberof rowsof
holesin the paperrecord,a binary codesystemis used
for all the operations
employingthepaperrecord.Relay
OUTPUT
trees are usedfor the binary conversionsystem.The
relaytreesystems
usedin the electronic
musicsynthesizerare shownin Fig. 4. Usingfour rowsof holesin the
paperrecord,it is possibleto selectsixteendifferent
TO PAPER
R ECORD DRUM
Fro. 5. Schematicblock diagram of the fundamental frequency
operations.
sourceconsistingof the variableand fixedoscillators,switchboard,
The soundsourcesfor the master frequencysource and relay tree.
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314
OLSON,
BELAR,
AND
TIMMENS
quencyis a functionof the direct currentinput. The
output is fed to an amplifierand pulsegenerator.The
INPUT
outputof the pulsegeneratoris oppositeto that of the
DIVIDERS
pulseof theincomingsignal.The systemis a comparison
ililllll!1111111
systemin whichthe frequencyof the oscillatoradjusts
itself to the input frequency.If the input frequency
OUTPUT
changes
from onefrequencyto a differentfrequencyin
a discontinuousstep, the direct current oscillator
TO PAPER
changesfrom this frequencyto the new frequencyin a
RECORD DRUM
continuousmanner.The comparisonsystemcan be adFro. 6. Schematic
blockdiagramof the octaverconsisting
of the justed so that the glide is accomplished
in a smooth
frequencydivider and relay tree.
transition or in a series of approximationsby the
amountof amplificationbetweenthe oscillatorand the
FREQUENCY
Ce TO Be
scaleof four multipliers.Thereare alsotwo setsof secondpulsegenerator.
twelvevariablefrequencyoscillators
and a noisegenThe glidesystemwill executea singletype of glide
erator,as shownin Fig. 5. The twelvefixedfrequency withoutany outsidecontrol.However,if it is desiredto
sources
makeit possible
to operatein the equallytem- havethe glidechangein any part of a musicalselection
peredscale.The useof the twosetsof twelvevariable beingsynthesized,
the changesmay be controlledby
frequency
oscillators
makesit possible
to usethe just
scaleaswellasanyotherscaleby pretuning
thevariable
INPUT[
ELECTRONIC
I OUTPUT
frequencyoscillatorsto the desiredfrequency.For
FREQUENCY
I
GLIDER
[FREQUENCY
example,all threesetsof oscillators
canbe usedtoset
up a micro-scale
of up to 36 tonesto the octave.Still
RELAY
TREE
finer graduationsare possibleby retuningbetween
separate
takes.The tunableoscillators
alsopermitthe
useof anyarbitraryreference
frequency
insteadof the
IIIIIII1'1111111
t
TO PAPER
RECORD
ORUM
standard A-440. The random noise source is useful in
providinga largenumberof variouseffectsin theper-
z..J
cussioncategories.
Thefundamental
frequency
sources
providethetones
TIME IN SECONDS
I•
TIME IN SECONDS
in oneoctave.The octaverdepicted
in Fig. 6 consists
of
frequency
dividers
for providing
frequencies
fromCoto
B9,inclusive.
Thecombination
of thesystem
of Figs.5
,.o,o
I
•z
a::z
and6 makesit possible
to selectanyfrequency
in the
C
TIME IN SECONDS
D
TIME IN SECONDS,
rangefromCoto B9,a totalof 120separate
frequencies
by meansof eightcircuits,
eightbrushes,
andeightrows Fro. 8. Schematicblock diagramof the electronicglider, relay
tree, and typical frequencyglides.
of holesin the paperrecord.This showsthe advantage
of a binarycodingsystemin reducing
the numberof
rowsofpunched
holesrequired
in thepaperrecord.For meansof a relay tree actuated by contactsand a row
example,
in the eighty-eight
noteplayerpiano,eighty- of holes,as shownin Fig. 8.
eightrowsofholesin thepaperrecordareusedto select A few typical glidesare shownin Fig. 8. The frethe frequency.
quencyglideof Fig. 8(A) depictsa relativelyrapidand
A blockdiagramof a frequency
glidesystem
isshown smoothtransitionfrom one frequencyto anotherfrein Fig.7.Whentheinputfrequency
issuddenly
changed quency.The frequencyglideof Fig. 8(B) depictsa relafrom onefrequencyto anotherfrequency,the output tively slow and smoothtransitionfrom one frequency
glidesin frequency
in a continuous
mannerfromone to anotherfrequency.The frequencyglidesof 8(C) and
frequency
to the otherin the following
manner.The (D) showthat the secondfrequencyis approachedin a
incoming
signalis amplified
andconverted
intoa series seriesof approximations.
Normally the glider is not connectedto a paper
of negative
pulses.
Thepulses
aresentthroughan inteto usefour
gratoranda lowpassfilter.Theresultantdirectcurrent recorddrum,(Fig. 2). However,it ispossible
is amplified
andfed to an oscillator
in whichthe fre- circuitsin the codingsystemand therebyprovidesixteendifferentglidesfrom a presetcondition.Of course,
A
Fro. 7. Schematicblockdiagramof the frequencyglider.
an infinite numberof glidesare possiblein presetting
the systemof Figs. 7 and 8.
Means are alsoprovidedin the frequencyglider to
flattenor sharpenits outputby about-} toneunderthe
controlof thepaperrecord.Thisis usefulwhenthe glide
itselfshouldbe relativelyrapidbut the final approach
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ELECTRONIC
MUSIC
to the exactfrequencyvery slow.This facility has also
beenusedto generatemicro-scales.
An electronicsystemis usedfor the growth, duration,
and decaycharacteristics.
The block diagram of Fig. 9
shows that it is possibleto obtain sixteen different
growth, duration,or decaycharacteristics
from a preset
condition.Of course,it is possibleto obtain an infinite
number of preset growth, duration, and decay characteristicsin the systemof Fig. 9. In an electronicsystem
it is possibleto obtain growth and decay characteristics
which are exponentialfunctionsas well as all manner
of other functions. A few of the typical growth and
decaypatternsare shownin Fig. 9. The graphA of Fig. 9
depictsa growth and decay characteristicdescribedby
exponential functions. The growth and decay are
moderatewith respectto time. The graph B of Fig. 9
depictsa very rapid growth characteristic.The decay
characteristicis an exponentialfunctionwith a sudden
SYNTHESIS
315
ELECTRONIC
l OUTPUT
INPUT
VOLUME
CONTRL
I
'
IIIl'111111111111
RELAY
TREE
FIG.
10.
TO PAPER
RECORD
DRUM
Schematic
block diagram of the
electronic
volume
con-
trol system and relay
tree and typical input vs
output characteristics
and the output vs time
characteristics.
0
I
2
3 4
5 6 7 8
INPUT
9
I0 II
12 13 14
STEPS
'l
TIME
IN SECONDS
•[•T[M
ELECTRONIc
Sy
GROWTH
INPUT
OUTPUT
DURATION
DECAY
ting the over-all volume range. A few of the typical
output vs time characteristics
are shownin Fig. 10(B).
As thesecharacteristicsshow, the volume may remain
constantor may vary during the soundingof a tone.
A low frequencymodulator is provided as shown in
Fig. 2 for producinga vibrato or tremolo.The modulation frequencymay be varied over the frequencyrange
of from 5 to 10 cyclesper sec.
The output of the octaverproducesa sawtooth wave
RELAY
TREE
Fro.
9. Schematic
TO PAPER
block diagram of the
electronic growth,
duration, and decay
RECORD
system
andrelaytree
andtypicalgrowth,
duration,
anddecay
characteristics.
DRUM
which contains the fundamental
,.,
A
C
TIME
TIME
IN SECONDS
IN
SECONDS
O
TIME
IN
SECONDS
TIME
IN SECONDS
decreasein the decayrate during the decayperiod. The
graph C of Fig. 9 depictsdiscretechangesin both the
growthand decaycharacteristics
duringthe growthand
decay cycles.The graph D of Fig. 9 depictsrelatively
long growth and decay characteristics.
The growth, duration, and decaysystemperformsa
doublefunction, namely, it opensand closesthe synthesizerchanneland controlsthe growth,duration,and
decay.That is, all the elementsof a synthesizerchannel
are establishedbefore the systemis unblockedby the
growth system.
An electronicsystemis usedfor the volume control
systemdepictedin the block diagramof Fig. 10. The
amplificationof a pentagridconvertertube with variable transconductanceis a function of the bias voltage
appliedto the controlgrid. The controlvoltageis supplied by the relay tree from a direct current power
supply. Typical input vs output characteristicsare
shownin Fig. 10(A). Controlsare providedfor preset-
and all the overtones.
The spectrumof a saw tooth wave having a fundamental frequencyof 440 cyclesis shownin Fig. 11. The
timbre controlsystemshownin Fig. 12 employingfilters
and resonatorchainsprovidesa meansfor changingthe
timbre or overtonestructure. Practically any overtone
structurewhatsoevermay be obtainedby meansof the
frequency discriminating systems employed in the
timbre control system. A few typical examplesof the
overtone structures which may be obtained by the
timbre control systemare shownin Fig. 12.
The paper record is punched by means of the key-
o
'40
4
8 IO
s
FREQUENCY IN CYCLES PER
5
ECOND
4
e •oø
F•G. 11. The frequencyspectrumof a saw tooth wave with a
fundamental frequencyof 440 cyclesper sec.
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316
OLSON,
BELAR,
LOWP•SS
F-'--'• H
,GH
pASS
]i--•l'"'2"'-'tF
• INPI•IT
I m
J-...-4 SWITCH
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"' •
I l:=:q
c.,•,.•
F=:tl=:qt
TO PAPER
RECORD DRUM
I
FR EOUENCY
I
FR EOUE N CY
AND
TIMMENS
speed of 4 in. per sec was chosenfor this selection.
The correspondingmeasuresin conventional musical
notationare alsoshownin Fig. !4. The rowsof holesare
numberedlike the keys of Fig. 13 in the binary code
numbering.Referring to Fig. 14, it will be seenthat the
codingof the left half is for onesynthesizerchanneland
the codingon the right for the othersynthesizerchannel.
Referringto the growth,duration,and decaycoding,it
will be seenthat the notesare executedalternately by
the first and second channel. Figure 14 shows the
changesin growth, decay, and volume which are the
synthesist'sinterpretation of this musical selectionas
called for in detail by the coded information shown
below the conventional
I
music notation.
[ 11,,
When the two paperrecordshave beenpunchedand
œRœOU!•NCY
FREOUENCY
the settingsof the various elementsof the synthesizer
have beenestablished,the next step is the recordingof
Fro. 12. Schematicblock diagram of the timbre control system
The two diskphonograph
consistingof switchboards,low and high pass filters, resonator the output of the synthesizer.
chains,and relay tree.
recordersare shownin Figs. 2 and 3.
The synthesizerispurposelylimited to the production
boardpunchingsystemshownin Fig. 13. The keys are of four simultaneous tones. The reason will be evident
coloredto facilitatethe operationof punchingthe codes. in the descriptionwhich follows.In general,becauseof
The note-selecting
groupof 1, 2, 4, and 8 are red. The the buildup and decay characteristicsof most musical
octave group is yellow. The growth, duration, and sounds,the systemis actually limited to two musical
decay group is blue. The timbre group is gray. The tones.That is, each codedpaper recordcan producea
musicalsequenceof tones.Thus, it will be seenthat if
volumecontrol groupis black.
Referringto Fig. 13, it will be seenthat the punched more than two musical tones are required that some
recordconsistsof rowsof holes.Each row of holespasses meansmust be providedfor combininga large number
under a brush.When the brushpassesover a hole, the of musicaltoneswhichare soundedsimultaneously.The
brush makes contact with the drum, and as a result
sixteen-inch
disk record
can accommodate
six three-
havebeen
closesthe actuatingcircuitin the relay tree. Each brush minuterecords.After sixcompleterecordings
is equippedwith severalspringsarrangedso that the made, the six recordingsof one recordcan be combined
brush never breaks contact With the drum before
into a singlerecordingby meansof the two turntables
making contactat the adjacenthole. Thus, a row of and the arrangementshownin Fig. 15.
The two turntablesare electricallyand mechanically
holeswill provide continuouscontact and at the same
time give the sameresultas a slot in the paper.Slots interlockedthiough the motorsand generatordriven
cut in the paper will resultsin a very weak recordthat from a master motor which insures absolute synchronismbetweenthe two turntables.The recordcontaining
can be easilytorn and with poorlateral rigidity.
A simple punchedrecord for playing a phrase of the six programsis reproducedby meansof six pickups
"Obelin" is shownin Fig. 14. The record is drawn to and the output of the pickupsfed to a mixer amplifier.
The mixer providesmeans for adjusting the balance
scaleand has the length indicated in inches.A paper
amongthe six recordings.The output of mixer amplifier
is fed to the recordingamplifier.The output of the recordingamplifier is fed to the cutter. In this way six
original recordscan be combinedinto one record.This
processcan be carried on and practically any number
of musical tones can be combined.
The final completeselectionis recordedon magnetic
tape. If there are twelve or lessmusicaltonesthe two
recordscan be reproducedfrom the two turntablesand
recordedon magnetictape without any additional disk
recordingprocess.
PRODUCTION
OF MUSIC
MUSIC
Fro. 13. The keyboardpunchingsystem.
BY MEANS
OF ELECTRONIC
SYNTHESIZER
The electronicmusicsynthesizerdescribedin the proceding sectionprovidesmeans for producingall the
characteristics
of a tone' namely,frequency,intensity,
Downloaded 18 Feb 2013 to 160.39.22.56. Redistribution subject to ASA license or copyright; see http://asadl.org/terms
ELECTRONIC
as
FREQ.
MUSIC
OG"rAVE ENVEL
as 112481
248
TIMBRE
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FIG. 14. A copy of the paper
record containinga phrase of
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growth,duration,decay,frequencyglide,waveform, the musicalscorewith the specificnotationshas been
andvibrato.Whenthesynthesizer
isusedby musicians, completed,as shownin Fig. 16, the next step is the
these are the characteristics of the tone which must be
transfer from the musical score to the code.
specified.
At firstglanceit wouldappearthat theuseof
Any musicalscoreis itselfa codedpresentationof the
the electronic
musicsynthesizer
for the production
of cornposer's
work which, before it can becomemusic,
music would be a very complexand cumbersomerequiresfurtherinterpretation.
Many factorsincluding
process.
On the contrary,the useof the synthesizer
is
a simpleand straightforwardprocedure.It is the
purposeof this sectionto describe
the productionof
recordedmusicfrom a musicalscoreby meansof the
electronicmusicsynthesizer.
The first stepin the electronicsynthesis
of musicis
theevolution
of themusical
scoreby the composer
or
arranger.The composeror arrangerdeterminesthe
RECORD
õ
RECORD
PICKUPS
'•
varioustonestructures
whichwill be employed
to pro-
URNTABLE
ducethe first product.He writes the musicalscorefor
each of these series of tones. The musical score carries
the specific
information
on the scale,frequency,
and
duration of the tone. The musician indicates on the
MOTOR
:'• GE••
115¾
AC.•
MASTER
MOTOR
MOTOR
Fro. 15. A schematicdiagramof a systemconsisting
of two
musicalscorethe growthanddecayandthe timbre.He
synchronized
turntables,records,pickups,mixer, amplifier,and
alsoindicatesglidesandvibratoif theseareused.When cutter for combiningseveralrecordingsinto onerecording.
Downloaded 18 Feb 2013 to 160.39.22.56. Redistribution subject to ASA license or copyright; see http://asadl.org/terms
318
OLSON,
BELAR,
SCRATCHER
x-x
xxx:
x
..............
x
x
xx
x
x
x
x
x
x
x
x
•, •, •,;
x
•,
•
, , ,,,,
BUNGO PNEUMATICO
ß
,x
,x
•x •
AND
TIMMENS
pletedexperiments
weremadewith shortsections
trying
differentenvelopes
of sounds
in thepercussion
category,
that is, envelopeswith rapid growth followedimmediately by a periodof decay.After selectingresonators
and filters which gave the desiredresult, the next task
was the determinationof an envelopenormally associated with a lip reed instrumentbut still usingthe
soundsourceand timbre quality selectedfor the percussive sound. The result is a nonexistent instrument
BASS
,
•
ff •
h,
,
ONE OCTAVE LOWER
CONGA
Y Ix ß
" •
•
Ix .x
which was dubbedBongoPneumatico.The resultant
soundsuitedthe genreof the selection;soit wasdecided
to use it. Having establishedin similar manner various
otherinterpretations,
a schedule
wasmadeshowingthe
generalclassification
of the soundcategories
by which
the scorewasinterpreted. The classificationscheduleis
depictedin Fig. 17. The numberof setupsandpartsare
determinedfrom the schedule
of Fig. 17. The procedure
CLAVlS
SECONDS
10
0
Fxc. 16. Excerpt from musicalscorefor "Obelin"
composedby Jim Timmens.
artistic considerationsenter into the problem of interpretation making this the most difficult part of synthesis,but alsothe most rewardingfrom the viewpoint
of the unlimitedpossibilities
offered.Oncethe interpretation is made, the rest of the work canbe donesystematically as will be shown.Returning to the example,
of which scorean excerptis shownin Fig. 16, it was
decided to synthesizea rhythm section in the Latin
Americanstyle which would soundplausible,but not a
copy of any existinginstrumentexactly?The aim was
to performan experimentin creatingmusicwhichwould
be commericalin today'smarket, not too differentyet
still possessing
novelty.Beforethe scorehad beencom-
20
40
30
50
60
I
1
I
1
CLAVI $
PT.
2[
I
I
I PLUCKED
STRING
CONGA
I
I
I
I
8ASS
8ASS
pNEuMATICO
BONGO
I
I
I
I
I
I
I0
20
30
I
40
I
50
60
TIM E { S ECONDS •
Fzc. 18. Organizationof the parts for "Obelin."
X
X
is carried out by consideringthe number of different
sounds which must appear simultaneouslyin the
finishedselectionandthe resultantsetupsrequired.The
organizationof the parts for the sample selectionis
shownin Fig. 18. The writing of the individual parts is
the next step.
Techniqueswere developedto set forth the specifica-
X
X
tions in both conventional
--
o • o ,-,o • • g • •,
CLAVIS
X
X
X
CONGA
X
X
X
X
8ONGO
X
X
X
X
BUN'GO
PNEUMATICO
X
BELL
X
BASS
X
SCRATCHER
X
X X
X
X
X
X X
X
musical and coded technical
X
terms.The latter includesthe desiredinterpretationand
PLUCKED STRINGS
X
X
X
X
follows in a more detailed manner the precept of the
MELODY
X
X
X
X
X
performancescore developedby Carl E. Seashore.
a
Fro. 17. General classificationof nine sound categoriescalled Figure 19 showspage one for part 6 which carriesthe
for in the musicalscorefor "Obelin" by Jim Timmensas arranged melodyfor "Obelin."
for the electronicmusicsynthesizer.
Referringto Fig. 19, the bars denotingthe measures
2 Except from a purely scientificviewpoint there is no interest
and no desireto create musicwhich can be producedby conventional means.The added effort and the new employmentof musicians capable to perform synthesisis warranted only if it can
producesomethingnew or better in the art of music.
in conventional
notation
are numbered.
The
distance
betweenbars represents16 rows of holesin the paper
a C. E. Seashore, Psychologyof Music (McGraw-Hill Book
Company,Inc., New York, 1938).
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ELECTRONIC
MUSIC
319
SYNTHESIS
recordinto whichthe informationis to be punched.At
a paperspeed
of 4 in. persecandwitha normalhole
spacing
of fourto theinch,thismeans16holespersec
willpassunderthebrushes
in theplayingof thispart.
Thenormallengthfor a quarternoteis thenfourholes
or oneinchin orderto play at a metronome
speedof
240quarternotesto theminute.Thetimeat whichthe
growthof a noteis to beginis interpreted
in thefirst
3
tabulationunder the staff.Thus, any deviationdesired
canbespecified.
Thenextcodespecified
istheenvelope.
In the examplegiven,it was decidedthat this part
shouldbe of sustained
tonescapableof beingvariedin
GLIDE
GLIDE
TIME• 7
3UR
6
I0
TIMB.
I
-,,'
6
3*/,61/,9112/314V,
I '•
I0
2
VOL.8(14>10<14>8:>I
8<14•8•11
.•#--'•
_
loudness
duringthe sounding
of a noteandhavedifferentdegrees
of attack.Accordingly,
a setupwasmade
providing
fordifferent
ratesofgrowth
according
to the
I•
ß
,•>
,•
'p
:
L__• LD
number called for in the schedule.The decay inherent
TIMEI
ENV.
DUR.
8I
in the instrumentwasarrangedto be alwaysaboutthe
samein time constantbut the durationbetweengrowth
GLIDE
• 7
•
....
r
i ,- •
2
I
I
6
8• 8<•8(,
8
8
6>4
I'
I
i
2
i
F r
, p •
I0
8 •
r-
14
r
, • t •
:GLIDE
II 121315
1311.3
124
TIMB.
I '-*'4•
VOL 8<10>8•
4• 6•8<12
56 7 II 15 I
3114 I 3 • 38I 3
4•6t10>t2•10>8,8
9
2I
4
4
10>8,8<14>8,8<11
anddecaywasmadeunlimited.
Theduration
itselfwas
specified
in thethirdrowof thecodetabulation.
It may
be noted that the duration of similarnotesis not always
specified
to beof thesamelength.
Thesedeviations
are
oneof the aspectsof interpretation.
For the duration of the four measuresshown in Fig.
19,the timbrewasthe sameandspecified
ascode1.
The actualtimbrefor that portionwasproducedwith
Fzc. 19. Synthesizer
codesheetfor Part 6, page1,
of "Obelin". MM' quarter note= 240.
a harmonic
spectrum
containing
allharmonics
diminishingwiththeirorderbutwiththehigherorders
reduced similarorderandfinally all recordedon differentbands
moredrastically.The last tabulationof codesconcerns of a 16-in.lacquerrecord.Reverberation
wasthenprovolume.The volumeis nearly alwayschangingas it grammed
for the partsselected,
finaladjustments
were
wouldwith a lip reedor bowedinstrumentwith some made,andthe overallcombined
on tape.Copiesof the
taperecordhavebeendemonstrated
to manyaudiences
expression.
Figure14shows
howthedirections
outlined
on the both in Princetonand during varioustalks given on
part of Fig. 18 werecarriedoutin punching
out the RCA Laboratoriesactivities all over the country and
papertaperecord.
Timenowbecomes
a longitudinalhave receivedmany favorablecomments.
dimensionmeasuredin inchesor in holes.The frequency
of eachnote is determineddirectlyfrom the musicno-
tationwhichis easilylearned.The onlydifference
be-
ACKNOWLEDGMENTS
Acknowledgments
areduemanywhocontributed
to
tween the notation and the suggested"American the work describedduring the time coveredin this
Standardfor Subscripts
TMis that in orderto makeall paper.RichardMaltby,thewell-known
bandleaderand
relaytreeshavethesame
numbering,
Co=16.352
cycles recordingartist then with RCA Victor, contributed
is denoted
by C•; but sinceoctaves
canbe switched
at originalcompositions
and arrangements;
Mr. R. A.
will manually,this is no greathandicap.
Lynn followedthe designand construction
of the
Otherspartsthanthe oneshownwereproduced
in Mark II electronicmusic synthesizer;L. Buttefloss
did much of the construction;and G. M. Schmelz,
4H. F. Olson,MusicalEngineering
(McGraw-HillBookCommuch of the encoding.
pany,Inc., NewYork, 1952).
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