Sequential PROPHET-600 User manual

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OPERATION MANUAL
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MODEL 600
Manual No. CM600A
PROPHET-600 SYNTHESIZER
OPERATION MANUAL
By Stanley Jungleib
Sequential Circuits, Inc.
Nijverheidsweg lie
3641 RP Mijdrecht, Netherlands
02979-6211
TELEX: 12721 SQNTL NL
Sequential Circuits, Inc.
3051 North First Street
San3ose, CA 95134-2093
408/946-5240
TELEX: 364412 INTR 706
~*\

PROPHET-600 SYNTHESIZER
OPERATION MANUAL
By Stanley Jungleib
Manual No. CM600A
Issued: December, 1982
Copyright ©1982 by
SEQUENTIAL CIRCUITS, INC.
All rights reserved. Printed in USA.
i
The contents of this manual are the property
of SCI and are not to be copied or reproduced
without our prior written permission.
Please return your warranty card!
.
aCM600A 12/82

About the Prophet-600
Early in 197S Sequential Circuits revolutionized the art of keyboard synthesis by
introducing the Prophet-5, acompact instrument intended for the performer. Before
the Prophet appeared it was not possible for a keyboardist to instantly select custom
synthesized sounds and play them polyphonically. Its featured programmability used
emerging microcomputer technology to allow complete and instantaneous control over,
essentially, five complete synthesizers (voices). The Prophet-5 became the leading
instrument of its kind.
Now technology has developed to the point where SCI can offer the six-voice Prophet-
600, which sounds basically like aProphet-5, at less than half its price. It has the
capacity for 100 sound programs. All programs can be fully customized (edited) and
stored internally, or on audio tape via the built-in cassette interface. The Prophet-600
adds aflexible arpeggiator and a**00-note, real-time polyphonic sequencer, which
remembers whatever you play.
The Prophet-600 actually contains six individual synthesizers, termed "voices." For its
principle sound sources, each voice contains two voltage-controlled oscillators (VCOs),
referred to as OSC Aand OSC B. OSC Aand OSC B can be mixed into aresonant low-
pass voltage-controlled filter (VCF). The filter modifies the voice timbre under control
of its four-stage envelope generator. The filter may also serve as a sound source.
Following each filter, avoltage-controlled amplifier (VCA)—also controlled by afour-
stage envelope generator—shapes the voice amplitude. Only one voice is depicted on
the control panel, because the voice controls "patch" the six voices identically. This
makes the voices homophonous—they sound alike—with pitch differences corresponding
to (at most) six simultaneously-held keys.
Supplementing the basic voice are polyphonic modulation (POLY-MOD) signal routings
within each voice that allow OSC Band the filter envelope generator to function as
modulation sources applied to OSC A or the filter cutoff frequency. There is asingle
low-frequency oscillator (LFO) which can modulate all six voices to a depth adjusted
by the modulation (MOD) wheel. The PITCH wheel can be used to raise or lower the
pitch of all voices by the same interval.
The term "digital-analog hybrid" is often used to describe the Prophet synthesizers.
This means that rather than directly controlling, the analog synthesizer voices, the
keyboard and most controls are actually devices which input "data" to amicrocompu-
ter system which in turn "programs" the voices. This microcomputer system has
several important functions. It solves the problem of generating six independent sets
of voice control voltages and gate signals (which operate the envelope generators)
from asingle keyboard. In fact, in the Prophet-600 the (formerly) analog envelope
generators and LFO have been entirely replaced by computer system functions. The
digital memory provides away to store all of the switch and knob settings which form
aprogram, and the keystrokes which form sequences. The programs and sequences are
retained even when the Prophet is turned off, thanks to asmall battery with a10-year
life. Finally, the microcomputer system keeps the twelve voice oscillators in tune.
CM600A 12/82 in

Contents
INSTALLATION
1-0 GENERAL
1-1 HANDLING
1-2 LINE VOLTAGE SELECTION AND FUSING
1-3 POWER CONNECTION
1-4 AMPLIFIER AND SPEAKER CONSIDERATIONS
1-5 AUDIO OUTPUT
1-6 FOOTSWITCH
1-7 CASSETTE
1-8 FILTER CV IN
1-9 MIDI
Page
1-1
1-1
1-i
1-2
1-2
1-4
1-4
1-4
1-5
i-5
BRIEF INSTRUCTIONS
2-0 PRESET MODE
2-1 PROGRAM EDIT AND RECORD
2-2 UNISON
2-3 ARPEGGIATE
2-4 SEQUENCER
2-5 SAVE TO TAPE
2-6 LOAD FROM TAPE
2-1
2-1
2-1
2-2
2-2
2-2
2-3
BASIC OPERATION
3-0 GENERAL
3-1 POWER ON
3-2 PREPARATION
3-3 PITCH AND MOD WHEELS
3-4 RETUNJNC
3-5 VOICE ASSIGNMENT
3-6 UNISON AND GLIDE
3-7 IN CASE OF DIFFICULTY
3-1
3-1
3-1
3-3
3-3
3-3
3-4
3-5
ARPEGGIATOR
4-0 INTRODUCTION
4-1 MODES
4-2 ARPEGGIATE UP/DOWN
4-3 ARPEGIATTE ASSIGN
4-4 NOTES ON USAGE
4-1
4-1
4-1
4-2
4-2
SEQUENCER
5-0 INTRODUCTION
5-1 RECORDING
5-2 PLAYBACK
5-1
5-1
5-2
IV CM600A 12/82

PROGRAMMING
6-0 INTRODUCTION
6-1 EDIT MODE
6-2 MANUAL MODE
6-3 RECORD MODE
SYNTHESIZER CONTROLS
7-0 INTRODUCTION
7-1 OSCILLATOR A
7-2 OSCILLATOR B
7-3 GLIDE
7-4 MIXER
7-5 FILTER
7-6 ENVELOPE GENERATORS
7-7 AMPLIFIER
7-8 LFO-MOD
7-9 POLY- MOD
6-1
6-2
6-3
6-3
7-1
7-3
7-4
7-4
7-5
7-5
7-6
7-7
7-8
7-9
CASSETTE INTERFACE
8-0 INTRODUCTION 8-1
RECORDER AND TAPE SELECTION 8-1
PRECAUTIONS 8-2
SAVING PROGRAMS OR SEQUENCES TO TAPE 8-3
LOADING PROGRAMS OR SEQUENCES FROM TAPE 8-4
S-l
8-3
9SCALING 9-1
10 MIDI
10-0 INTRODUCTION
10-1 BASIC OPERATION
10-2 CONNECTION/INITIALIZATION*
10-3 KEYBOARD INFORMATION
10-4 PROGRAM SELECT
10-5 MOD WHEEL
10-6 PITCH WHEEL
10-6 PROGRAM DUMP
10-1
10-1
10-1
10-2
10-3
10-3
10-4
10-4
1 1 FACTORY PROGRAMS Il-l
12 MAP/PANEL BLANKS 12-1
CM600A 12/82

INSTALLATION
1-0 GENERAL
This section describes installation procedures and connections which can be made to
the back panel of the Prophet-600. See Figure 1-0. All connectors are standard 1/4-
inch phone jacks, except for the MIDI, which uses 5-pin DIN connectors.
CAUTION! Do not connect the Prophet-600 to power or switch power
on before following the instructions below.
1-1 HANDLING
The Prophet-600 is asophisticated device containing state-of-the-art microcomputer
and analog circuitry. It should be treated with as much care as you would provide an
acoustic instrument. Avoid temperature and humidity extremes. Shock or constant
vibration can damage the keyboard or controls, and can loosen connectors or socketed
integrated circuits. If you expect to transport the Prophet-600 regularly, it is
imperative to invest in aprofessional "road" or "flight" case for it. These are made by
several manufacturers and should be carried by your music dealer. If you can't find a
case, please contact the SCI Customer Service Department.
1-2 LINE VOLTAGE SELECTION AND FUSING
CAUTION! Check line voltage selector before switching power on.
Disconnect power before switching line voltage.
The Prophet-600 has apower fixture on its back panel to which its three-wire power
cable attaches. There is also aline voltage selector switch and fuse holder. Prophet-
600s shipped in the U.S. and to Japan are usually set at the factory for 110V; to
Europe, 220V.
If the selected voltage does not match the line voltage, disconnect the power cord and
switch the voltage selector. Replace the fuse according to the selected line voltage:
110V
220V 1/2A, slo-blo 1/4A, slo-blo
CM600A 12/82 l-l

1-3 POWER CONNECTION
WARNING! It is up to you to check the power and ground
interconnections of the Prophet-600 and ail other instruments and
equipment you use to prevent potentially lethal shocks. Sequential
Circuits, Inc. is not responsible for any equipment failure due to
incorrect AC power connections, and is not liable for any personal
injury due to electrical shocks as a result of unsafe grounding practices.
The Prophet-600 comes with athree-prong power plug to insure safe grounding with
other equipment. The ground prong is connected directly to the metal chassis. Because
of this AC ground, a"ground loop" will often be created when an audio cable is
connected between the Prophet-600 and standard amplifiers. As aresult, low-leve!
hum may occur. Defeating the AC ground with atwo-prong adapter will usually defeat
the hum but this practice can set up ashock hazard between the units. The hum levei
will depend on exactly how the synthesizer and amplifier are connected to the AC. For
minimal hum, use the same AC outlet for the Prophet-600 and its amplifier. This
should reduce the hum to an acceptable level.
1. Connect the power cable to the power fixture on the Prophet-600.
2. Check that the Prophet-600 power switch is in off position.
3. Connect the other end of the power cable to aproperly grounded three-prong outlet.
Don't defeat the AC-ground.
4. Plug all other equipment such as effects devices, mixers, amplifiers and recorders
into the same outlet.
WARNING! Do not overload. When in doubt, consult an electrician.
5. As you probably know, many older buildings and clubs are notorious for their poor
quality AC wiring. We therefore urge you to use one of the several available "ground-
checking" devices to verify AC connections.
\-U AMPLIFIER AND SPEAKER CONSIDERATIONS
This is an excellent time to think about your amplifier and speaker system. By
converting the synthesizer's electrical output into the potent vibrations you hear, the
sound system becomes part of the instrument. Of course you can use anything you like
and can afford. But obviously asynthesizer of this caliber should not be constrained by
aweak amplifier and muddy speakers.
Particularly because the synthesizer develops amuch greater dynamic range than the
typical audio source, agreater margin of amplifier headroom is needed to prevent
clipping, thus ensure the cleanest possible sound (and possibly preventing tweeter or
horn damage). In consideration of this it is not difficult to justify committing astereo
amp of 200W/channe] for performance. While amono arnp will suffice, astereo
1-2 CM600A 12/82

MIDI
FROM MIDI MASTER
(see secT/ov io/
•CONTROL TOOISWITCM
(Sef'AL Ne'i 1-75)
r~u ,-».rh.r\ r\ n. nn
&AUDIO
OUT
pRoptaet*6oo
FILTER
CV IN
o
-TO MIDI SLAVE
(see secrion /Of
POWER SWITCH
LINE VOLTAGE SWITCH —
•
tcuccK BEFOPe applying powcpi
n^-1
CASSETTE t
'H OUT X-
oooo o
STEREO, SOOJIMIN -0R-
SCI MODEL S40
NOT INCLUDED
(OP OTHeP VOLTAGE
PEDAL, O-tQVDC)
EAR. MONITOR,
LINE OUT MIC, LINE IN
(see text)
1
1
OTHE* .
KEY90ARDS
EFFECTS/
MIXER/
PRE-AMP
STEREO
AMP
<4
Figure 1-0
BACK PANEL CONNECTIONS
CM600A 12/S2 1-3

'
configuration will be able to take advantage of the numerous flanger/chorus and delay
units on the market. Alittle reverb does alot to enliven asynthesizer.
Speakers ought to be capable of handling the full amplifier power over the full audio
range (20 Hz to 20 kHz) without breaking up. If it is not practical to use amplifiers and
speakers specifically designed for electronic instruments or if volume must be kept
low, using your stereo system will generally give good high-frequency response. But if
you do this, be careful. Continuous playing of sustained synthesizer notes can cause
component amplifiers to overheat. Furthermore, the dynamic range of the Prophet-600
places stereo component speakers at some risk, because of powerful bass notes and
transients which will damage them if the volume is set too high.
1-5 AUDIO OUTPUT
CAUTION! To protect speakers, switch amplifier power off when
connecting the Prophet-600's audio output.
To drive apreamp or amp, astandard monophonic cable can be used. Or if there are
two audio destinations (perhaps one to remain "dry" while the other is processed), a
stereo cable may be more convenient.
The Prophet-600 has amonophonic output signal, but the jack is wired so that both
sides of standard stereo headphones can be driven. The headphones should have a
minimum impedance of 1200 Ohms per element (600 Ohms, in parallel).
1-6 FOOTSWITCH
Afootswitch is included which frees your hands from various control functions which
are explained elsewhere. On units with serial numbers 1through 75 the footswitch jack
is located to the far left (see Figure 1-0). The jack is placed near the CASSETTE jacks
on subsequent units.
Electrically, the footswitch is normally open? and closes when pressed.
1-7 CASSETTE
1. Connect CASSETTE IN to recorder output (EAR, MONITOR, LINE OUT).
2. Connect TO TAPE to recorder input (MIC, LINE IN).
Cassette interface operations are explained in Section 8.
1-4 CM600A 12/82

1-8 FILTER CV IN
This jack accepts a0-10 Vdc control voltage (CV) which raises programmed filter
frequency settings. This enables remote and spontaneous increase (but not decrease) of
brightness. This CV is usually provided by an accessory voltage pedal.
1-9 MIDI
MIDI stands for Musical Instrument Digital Interface, which is ameans for
interconnecting equipment from various manufacturers. For more information, see
Section 10.
1. Connect the IN jack to the MIDI OUT of the master sequencer or synthesizer.
2. Connect the OUT jack to the MIDI IN of the sequencer or slave synthesizer.
CM600A 12/S2 1-5

BRIEF INSTRUCTIONS
WARNING! Before using this instrument, read instructions in Section 1
concerning proper power connections and grounding.
2-0 PRESET MODE
1. Check that PITCH wheel is centered.
2. Check that MOD wheel is set to minimum (finger-slot towards you).
3. Play. Adjust VOLUME.
4. Check that MASTER TUNE knob is centered, or tune against another instrument for
A-440.
5. To switch programs (up to 99), press any two PROGRAM SELECT switches.
6. Use the PITCH and MOD wheels.
7. After afew minutes, press TUNE. Retune as needed.
For more information, see Section 3.
2-1 PROGRAM EDIT AND RECORD
1. Adjust knobs and switches to modify current program. Decimal point between
program digits lights, indicating Edit Mode.
2. To cancel changes, re-select program or press PRESET twice.
3. To record edited program, press RECORD then select desired program destination.
For more information, see Section 6.
2-2 UNISON
NORMAL: Switch UNISON TRACK up. Play.
CHORD TRACK: Hold chord. Switch UNISON TRACK up, or press footswitch (if
already in Normal Unison). To track adifferent chord, switch UNISON TRACK off,
then hold new notes, then switch UNISON TRACK on, or press footswitch.
For more information, see pages 3-4 and 3-5.
CM600A 12/82 2-1

2-3 ARPEGGIATE
UP/DOWN: Switch ARPEG UP-DN on. Hold keys. Adjust SPEED.
ASSIGN: Switch ARPEG ASSIGN on. Hold keys in the order to be arpeggiated.
LATCH: Press RECORD or hit footswitch.
STEP: Turn SPEED to -5 (fully counter-clockwise). Hit footswitch quickly, since the
arpeggiator will advance when the footswitch is released.
EXTERNAL CLOCK: Turn SPEED to -5. Connect clock to footswitch jack.
For more information, see Section i*.
2-4 SEQUENCER
RECORD: Switch RECORD on. Select SEQ Ior SEQ 2. Play. To stop recording, press
footswitch or RECORD. Sequence will playback. To stop, press SEQ 1or 2 again, or
press footswitch.
PLAY: Press SEQ 1or SEQ 2. To stop, press again, or press footswitch.
PROGRAM SPEED: During playback, adjust SPEED knob as desired. To program speed,
press RECORD.
For more information, see Section 5.
2-5 SAVE TO TAPE
1. Insert tape and rewind to start.
2. Press RECORD.
3. If storing only ten programs, press appropriate PROGRAM SELECT once, so the
second display digit is blank.
k. Start recorder in record mode, with level "at "0," or slightly into the red.
5. Press TO TAPE.
6. If storing sequences, press either SEQ Ior 2 (within 3seconds of TO TAPE).
7. When FROM TAPE blinks, stop recorder and rewind.
8. To verify, start playback.
9. Press the FROM TAPE switch.
10. When the FROM TAPE LED goes out, stop the recorder. The file has been recorded
and verified.
For more information, see Section 8.
2-2 CM600A 12/82

2-6 LOAD FROM TAPE
1. Insert tape and rewind to start.
2. Press RECORD
3. If loading only ten programs, press appropriate PROGRAM SELECT once,
'f. Start recorder in play mode.
5. Press FROM TAPE.
6. If loading sequences, press either SEQ 1or SEQ 2(within three seconds of FROM
TAPE).
7. When the FROM TAPE LED goes out, stop the recorder. The Prophet-600 is
reprogrammed.
NOTE: Acassette is included which contains the Factory Programs,
followed by two demonstration sequences.
For more information, see Section 8.
CM600A 12/S2 2-3

BASIC OPERATION
3-0 GENERAL
This section contains information essential for basic operation. The Arpeggiator,
Sequencer, Programming, the Synthesizer Controls, Factory Programs, and Cassette
Interface are each detailed in separate sections.
NOTE: If you have trouble with any of the following basic operations,
please see page 3-5, In Case of Difficulty.
3-1 POWER ON
1. Install the Prophet-600 according to Section 1, Installation.
2. Switch Prophet-600 power on with its back-panel switch, which is at the left as you
face the keyboard.
3. Switch power on to your preamp or mixer, if used, then switch amplifier power on.
3-2 PREPARATION
Please see Figure 3-0, next page. When power is first switched on, the TUNE switch
light-emitting-diode (LED) lights to indicate that the microcomputer is tuning the
oscillators. The rest of the control panel will remain unlit for these few seconds. The
Prophet-600 cannot be played while the computer tuning routine is in progress.
After afew seconds, when tuning is complete, the TUNE LED will go out and the
control panel will come to life. The PRESET LED.w.ill be on, indicating Preset Mode.
This means the computer is ready to "patch" the synthesizer voices according to any of
the 100 programs stored in the Prophet's microcomputer memory. Program 00 is
automatically selected at first. All of the "Factory Programs" shipped with the
Prophet-600 are listed in Section 11. You are encouraged to modify (edit) all programs
to suit your own purposes. To learn how, see Sections 6and 7.
But if you are like most people, you'll want to play the Prophet-600 before studying it.
To do this, simply press two PROGRAM SELECT switches to enable adifferent
program. The new program will activate when you enter the second digit.
CAUTION! Before playing any key, first check that the MASTER
VOLUME knob is reduced to 0. This may keep you from accidentally
blowing-out speakers or ears.
CM600A 12/82 3-1

PROGRAM
as
000
000
000
PROGRAM SELECT
•TO
TAPE
•
FROM
TAPE
TUNE
»
PRESET •
RECORD
SEQ SEO (ARPEG ARPEGi
2IIUPON |[A55tGM|
1?^
:*
55
SPEED
PROGRAM display: Indicates current program in Preset or Manual
Modes. Indicates Edit Mode by lighting decimal point between the
digits.
PROGRAM SELECT 0-9 switches: Used to select program numbers 00-
99.
TO TAPE switch: Used for initiating program and sequence storage
through cassette interface.
FROM TAPE switch: Used for verifying and loading programs and
sequences through cassette interface.
TUNE switch: Activates and indicates computer tuning of oscillators
and filters.
PRESET switch: When on, indicates the Prophet-600 is programmed
according to memory. When unlit, indicates Manual Mode.
RECORD switch: Used for storing programs or sequences, or initiating
tape interface operations. Also used to latch arpeggiator.
SEQ land SEQ 2switches: Selects sequence banks for recording or
playback.
ARPEG UP-DN switch: Controls arpeggiator by key position.
ARPEG ASSIGN switch: Controls arpeggiator by key order.
SPEED knob: Adjusts arpeggiator and sequence playback rate.
Figure 3-0
BASIC OPERATION CONTROLS
3-2 CM600A 12/82

While playing, gradually raise VOLUME until the synth can be heard. For optimum
signal-to-noise ratio, the Prophet-600's VOLUME knob should be set as high as
possible, while overall audio system gain is reduced with the power amplifier control.
The MASTER TUNE knob simultaneously adjusts OSC A and OSC Bpitch on all voices
over about aone-semitone range. It is used to easily tune the Prophet-600 to another
instrument, such as apiano. If no other instrument is in use, the MASTER TUNE knob
should be centered.
3-3 PITCH AND MOD WHEELS
The PITCH and MOD wheels to the left of the keyboard are performance tools which
may take some practice to master. The wheels are monophonic. That is, both wheels
affect all voices uniformly: all voices are pitch-bent by the same interval and
modulated to the same depth. An integral part of playing is using the wheels and the
synthesizer controls (for example, FILTER CUTOFF and ENVELOPE AMOUNT) for
expression through dynamic and timbral variations.
The PITCH wheel is normally left in its center-detent position, from which it is
possible to "bend" oscillator pitch up or down by about a3rd.
Check that the MOD wheel is down (minimum modulation). The MOD wheel sets the
modulation level. When not in use the wheel is left "down" and no modulation will
occur. When the wheel is advanced fully "up," modulation is maximum.
3-4 RETUNING
The microcomputer tunes the oscillators when the Prophet-600 is first switched on.
But as the instrument warms up, the temperature change causes the oscillators to
drift. So it will ocassionally be necessary to retune, particularly during the first few
minutes of operation. After 30 minutes or so the instrument should not have to be
retuned very often. On the other hand, the more often you activate TUNE, the more
accurate the tuning will be. You will soon learn to hear when the Prophet-600 needs to
be tuned.
To retune, simply press the TUNE switch. Except for this switch, the control panel will
go dark while tuning is in process. Retuning takes up to four seconds, depending on how
far out of tune the oscillators drifted since the last tuning. The more often you tune,
the less time each tuning takes.
When tuning is concluded, the Prophet-600 returns to exactly its state before the
tuning. (Even unrecorded Edit Mode changes are restored.) It may be necessary to
slightly readjust MASTER TUNE.
3-5 VOICE ASSIGNMENT
The microcomputer continuously assigns the six synthesizer voices to the most
recently-played keys on the keyboard. You can play a maximum of six keys at once. If
CM600A 12/S2 3-3

/*
more than six keys are held down at the same time, the computer will reassign i
earliest used voices first. For example: playing and holding C, D, E, F, G, A, and B
succession will result in D, E, F, G, A, and B being sustained, while the C
disappear when the Bis played. In other words, the Prophet normally operates on a
"last-note priority" system: each new note played is assigned to the earliest-used
voice. (If the same key is struck repeatedly, the microcomputer assigns the sam
voice.)
3-6 UNISON AND GLIDE
While switching through the Factory Programs, you may have noticed the Prophet-68
switching in and out of UNISON mode. There are actually three Unison modes.
Normal Unison: To enable, simply switch UNISON TRACK on, while no keys are held.
(RECORD must be off.) The current program will be switched to UNISON operation:
all six voices will be assigned to the lowest key played.
In Normal Unison, if more than one key is played at once, the lower will be sounded.
The keyboard will also change from multiple- to single-triggering. This keyboard mode
was conventionalized by the Mini-Moog monophonic synthesizer and requires—but also
allows—a somewhat different keyboard technique. Instead of retriggering with eac*
keystroke, the envelopes will only retrigger if the previous key is completely released
before the new key is pressed. This requires astacatto touch. By the same token, if
you play legato,the envelopes will only trigger on the first note, while the rest of the
phrase will be sounded by the sustain settings of the envelopes. (Unless the
Arpeggiator is in use.) With practice, this system allows you to selectively accent
notes by touch.
NOTE: Normal Unison can only be switched off with the
UNISON/TRACK switch (not with the footswitch).
Tracking Unison: Play and hold any chord, then switch UNISON TRACK on or. i
UNISON TRACK is already on, hit the footswitch once. This "latches" the chord, so
that any key you play becomes the root, while the upper intervals follow along (track).
A new chord can be latched by simply playing it, then either switching UNSION track
off and on, or hitting the footswitch.
NOTE: Tracking Unison can only be switched off with the UNISON
TRACK switch (not with the footswitch). If the footswitch is pressed,
this switches back to Normal Unison.
Normally you'll release all keys when switching programs. However, if keys are held
while switching from apolyphonic to Unison program, these keys will form atracked
chord. (Because keys are being held when the UNISON/TRACK switch goes on.) Thi
trick can be used to advantage as a combined program select/chord track action.
3-* CM600A 12/82

Single Voice Unison: Play and hold any one note, then switch UNISON TRACK on. In
effect, this assigns one voice for tracking. This will yield athinner sound than Normal
Unison, where six voices sound simultaneously.
Glide: Lastly there is the GLIDE knob, which operates identically whether the
keyboard is polyphonic or in unison. When set to 0, there is no effect, because the
oscillator control voltages are allowed to step instantly between the discrete voltages
required to sound specific pitches. As GLIDE is advanced, the rate at which the
oscillator control voltages change is decreased. This introduces "portamento" between
the notes, which can be subtle or quite extreme.
Because the six voices are assigned to each new note in rotation, the polyphonic glide
function is not easy to predict. The amount of voice glide is the difference between
the last and next note to which it is assigned. For example, if GLIDE is turned up and
all voices have been assigned to the bottom of the keyboard (by virtue of six different
low notes having been played there), and you then play notes each in the middle and
high ranges, the middle notes will "arrive" before the higher notes.
In any Unison mode, the voices glide at the same rate.
3-7 IN CASE OF DIFFICULTY
Power
If the Prophet-600 is receiving power, it will display program numbers, or the TUNE or
one of the TAPE switch LEDs will be lit.
If no LEDs are lit, either power is not reaching the unit or the fuse has blown.
Disconnect power cable and check fuse by opening fuseholder.
Check the power source by plugging in other equipment.
Examine the power cable for damage.
Audio
If the PROGRAM display lights but no sound can be obtained, check that PRESET is on
and that the VOLUME control is turned up.
Test the synth by simply connecting stereo headphones directly to the output.
If still no sound can be heard, try substituting the audio output cable with one known
to be good.
Check your amplifier by trying ahigh-level audio input such as another synthesizer or
tape deck.
CM600A 12/82 3-5

ARPEGGIATOR
4-G INTRODUCTION
The arpeggiator and sequencer (see next section) are keyboard memory features of
great usefulness in performance. Through them you can create automatic
accompaniments which free the hands for other uses. The keyboard can be played
normally while either the arpeggiator or sequencer are on. (They do not operate
simultaneously.) The footswitch assumes different functions according to the mode of
operation.
4-1 MODES
The Prophet-600 offers two arpeggiate modes: Up/Down and Assign. Up/Down Mode
sequences between any held keys according to their position, from low to high and
back down. For example, CEGBGECE G...
Assign Mode sequences between keys according to the order that they are played. For
example, CGEBCGEB. This allows the creation of intense riffs, without you
having to actually play them.
The arpeggiate (and sequence) rate is controlled by the SPEED knob.
The arpeggiator can be "latched," which means it continues to play keys even when you
remove your hand(s) from the keyboard.
4-2 ARPEGGIATE UP/DOWN
1. Press the ARPEG UP-DN switch. Its LED will light.
2. If only one key is held, there will be no arpeggiating. This allows monophonic lines
to be played normally, with the arpeggiator brought, in only when more than one key is
held down simultaneously.
3. Adjust the SPEED knob.
4. If desired, press either the footswitch or RECORD switch (which will not light) to
latch the keys. You can then remove your hand(s) and the keys will continue to
arpeggiate.
5. While the arpeggiator is latched, you can play along with up to five more keys,
which will'not be arpeggiated or latched..
6. To stop, switch ARPEG UP-DN off.
7. To re latch a new set of keys, simply hold them down and hit the RECORD switch or
footswitch again.
CM600A 12/82 4-1