Wine Country Prophet-10 1016.1 User manual

tUODEL 1016.1
Manual No. Ch11016B
PROPHET- 10 SY NTHES~~ER
OPERATION MANUAL
by Tom Darter
and
POLYPHONIC SEQUENCER
OPERATION MANUAL
by Stanley Jungleib
W~ne Country Productions. Inc.
1572 Park Ctesl Coun. Suite #505
San Jose. Calllornla 95118 USA
Phone [phone] FAX [phone]
SEQUENTIAL PflOducf Spec,aIisls Stnw 1987

PROPHET-I0 SYNTHESIZER
OPERATION MANUAL
by Tom Darter
Manual No. CMIOIOA
and
POLYPHONIC SEQUENCER
OPERATION MANIJAL
by Stanley Jungleib
Manual No. CM 101
50
Manual No. CM1016B
Issued: September, 198 I
~o~~ri~ht@l981by
SEQUENTIAL CIRCUITS, INC.
All rights reserved. Printed in USA.
The contents of this manual are the property
of SCI and are not to be copied or reproduced
without our prior written
permission.
-
NOTE. Write Prophet-lO/Polyphonic Sequencer serial number (on back panel) here:
Refer tothis number in all correspondence with the factory.
Please return your warranty card!

Table of Contents
SECTION IGETTING STARTED
1-0 INTRODUCTION
1-1 SET-UP
1-2 TURN-ON AND INITIAL TUNING
1-3 hlASTER OUTPUT CONTROLS
1-4 PRESET SELECTION
1-5 PITCH AND MOD WHEELS
1-6 TRANSPOSE SWITCHES
1-7 VOICE ASSIGNhlENT
1-8 RETUNING
SECTION
2 BASIC PROCEDURE5
2-0 INTRODUCTION: THE FRONT PANEL 2- 1
2-1 MODES OF OPERATION 2- 1
2-2 RECORDING PROGRAMS 2-2
2-3 KEYBOARD MODES AND UPPER/LOWER PANEL SWITCHES 2-3
SECTION 3THE PATCH CONTROLS
3-0 INTRODUCTION
3 LOICE SIGNAL FLOU
3-2 OSCILLATOR A
3-3 OSCILLATOR B
3-4 hllXER
3-5 FILTER
3-6 4MPLIFIER
3-2 EQUALIZATION
3-8 hlODCILATION
3-9 hllSCELLANEOUS
SECTION 4ACCESSORIE.5 AND THE BACK PANEL
4-0 INTRODUCTION
4 CONTROL VOLTAGE IN--PEDALS I AND 2
4-2 FOOTSWITCHES
4-3 MONOPHONIC SEQUENCER INTERFACE
SECTION 5POLYPHONIC SEQUENCER OPERATION MANUAL
SUB- SECTION IBASIC OPERATION
1-0 INTRODUCTION
1-1 Play~ngthe Dernonstrat~onSequences

1-2 REAL-TIME USE
1-3 PITCH and MOD Wheel Disconnect
1-4 Footsw~tch
1-5 Overflow
1-6 External Clock
1-7 GATEICV OUT
1-8 Trouble?
SUB-SECTION
2 TAPE OPERATION
2-0 INTRODUCTION
2-1 PRECAUTIONS
2-2 SAVE TO T.4PE
2-3 LOAD FROhl T.4PE
SUB-SECTION 3 MODES OFOPERATION
3-0 INTRODUCTION
3-1 Power-On
3-2 IDLE MODE
3-3 RECORD MODE
3-4 ln~t~allz~ngSequencer Programs
3-5 Real-T~meRecording
3-6 Single-Step Record~ng
3-7 PLAYB4CK MODE
3-8 Truncate
3-9 Append
3-10 EDIT hlODE
3-1 1 Slngle-Step Ed~t
3-12 S~ngle-SrepEvent Delete
SUB-SECTION
4 SINGLE-STEP APPLICATIONS
4-0 INTRODUCTION
4-1 DEFINING NOTES .4S STEPS
4-2 EDITING
4-3 PROGRAM CHANGES
.
SECTION 6SELECTED BIBLIOGRAPHY
SECTION 7THE FACTORY PRESET PROGRAMS
SECTION 8BLANK PATCH DIAGRAMS

GETTING STARTED
14 INTRODUCTION
The Prophet-10 contains twocompletely programmable polyphonic synthesizer banks, each havingfive
complete and individual synthesizer "voices." Although each voice
is keyed independently, all five
voices ineach polyphonic bank functionfrom the same patchsetting, and are thereforehomophonous.
However, each of the two 5-voice synthesizer banks can operate on
a completely different program,
and can be articulated independently via the two keyboard manuals. In other words, two different
programs can beused
at any onetime. One is the UPPER program,with one5-voice synthesizer usually
tied to the upper keyboard, and the other
is the LOWER program, with the other 5-voice synthesizer
usually tied to the lower keyboard.
Each synthesizer voice consists of two voltage-controlled oscillators (VCOs),
a white noise source, a
resonant low-pass voltage-controlled filter (VCF), a voltage-controlled amplifier (VCA), two envelope
generators (onewired to theVCF and onewired to the VCA) and
a 3-bandequalizer (EQ). Inaddition,
there are routings (via the POLY-MOD section) that allow for oscillator B and the filter envelope
generator lolunction as modulation sources which can beapplied to the frequency or pulse-width of
oscillator A, or the filter frequency. Finally,each 5-voice synthesizer bank has asingle LFO whichcan be
applied to
all of its voices for various effects.The two LFOs (UPPER and LOWER)can also becombined
(summed)and applied to bothpolyphonic synthesizers for other effects.
The Prophet also contains a microcomputer, which serves several purposes: it determines which voice
is assigned to which key, it keeps the voices in tune, and (most importantly)it remembers preset voice
patcheswhich may be instantly recalled to program the voices. These preset programs are retained by
the microromputer's memory even when the Prophet
is turned off, thanks to a small battery with
a 10-year life.
-
1-1 SET-UP
To set upthe Prophet-10,simply plug the power cord intoan AC outlet and connect the instrument to
an amplifier via the AUDIO OUT jacks on the back panel. Both balanced (XLR connector) and
unbalanced
('A" phone jack) outputs are provided. The MONO jack provides the output of all ten
synthesizer voices. The UPPER and LOWER jacks can be used to separate the outputs of the two
polyphonicsynthesizer banks for stereo effects.
The fixture for the removable power cord also contains the main AC fuse, facilities for selecting
between100,120,220,and 240 volts AC line levels, and an AC line filter. Prophet-10sshipped inthe USA
will beset
at 120,those shippedto Europe will beset at 220, and those shippedto Japanwill beset at 100.
The fuse used should match the AC setting: A 2-amp slo-blo fuse should be used for 110 and 120-volt
operation, and
a 1-amp slo-blo fuse should be used for 220- and 240-volt operation. (These
specifications are indicated on the power cord fixture.)
As with most electronic equipment, the Prophet comes with a three-prong power plug to insure safe
grounding with other pieces of equipment in use.The ground prong
is connectedto the chassisofthe
instrument. It
is upto you to check the ground connections of the Prophet and all other instruments
and equipment you use, to prevent potentially lethal shocks. As you probably know, many older
bulldings and clubs are not known ior their quality AC wiring, so we urge you to use one of the several
"ground-checking" devices available onthe market to verify AC connections.

Because of the AC ground, a "ground loop" will often exist when a cable is plugged between the
i
Prophet and an amplifier; as a result, low-level hum will often occur. Defeating the AC ground with a
two-prong adapter will usually eliminate the nolse, but
it can also set upa shock hazard between the
-
pieces of equipment. The amount of hum is dependent onwhere the two units are connected to AC.
For minimal hum, use the same outlet for both the Prophet and
its amplifier: with this set-up, the hum
will be low enough below thesignal level to be acceptable.The further away fromeach other the plugs
are connected to AC, the more humwill occur. The quality of wiring inthe wall and wall socket will also
affectthe amount of hum,
Here
is a summary of recommended procedures to follow when setting upthe Prophet-10:
1) Plug the Prophet into
a three-prongcutlet. Don't dcfeat he AC-ground.
2) Plug all other connected equipment (amplifiers, volume pedals, effects devices, and other
accessories) into the same outlet. (Warning: do not overload. When in doubt, consult an
electrician.)
3) Verify all equipment grounding with a ground tester.
SequentialCircuits
is nor responsiblefor any equipment failure due toincorrect ACconnections, and is
not liable for any personal injury due to electrical shocks as a resulc ofpoor grounding.
1-2 TURN-ON AND INITIALTUNING
The Prophet
is turned on via the POWER switch on the rear panel. After the instrument is turned
on, the front panel will be dark
- except for the TUNE switch - for approximately 15 seconds
while the computer tunes the oscillators. When tuning
is complete the front panel will light up
and the BANK-PROGRAM indicator (the digital display) in the PROGRAMMER section of the front
panel will display
"1-1" for both the UPPER and LOWER programming sections. This indicates that
the Prophet-10
is ready to play and that its voices are programmed according to the settings stored
in those locations in the computer's memory. In addition, the UPPER panel switch in the pro-
gramming section will be lit, indicating that the UPPER program
is displayed on (and connected
to) the front panel patch controls. (Although separate UPPER and LOWER programs can be used
at
any tme, there is only one set of front panel controls. Hence, only one of the two programs can
be connected to the front panel controls at
a time.)
1-3 MASTER OUTPUTCONTROLS
The MASTER VOLUME knob
is used to adjust the overall volume of the Prophet-lo's output.
The BALANCE knob
is usedto adjust the relative volume of the upper and lower synthesizer banks
The A40switch activates
3 built-in, crystal-referenced A-440 oscillator which is accurate to .1 Hz
in any environment. This reference oscillator
is enabled by hitting the switch - the LED indicator
in the switch will light. To turn the tone off, hit the switch again. (The A-440 signal
is routed
independently to both the upper and lower synthesizer banks. In order to be heard, the pro-
grammable VOLUME, MASTER VOLUME, and BALANCE knobs must all be set correctly
- as well
as any AMP footpedals.)
The MASTER TUNE knob
is used to adjust the overall tunlng of the Prophet-lo's output. Tune by
holding down
a key (e.g. middle A) and match~ngeither the A40reference or an outside pitch
source.

14 PRESET SELECTION
When turned on, the Prophet automatically enters PRESET mode, meaning that
it is ready to set
up the synthesizer's voices according to preset patches stored in the memory of the Prophet's
computer. Both the UPPER and LOWER presets are arranged in four banks of eight programs each
(UPPER
= 32 programs, and LOWER = 32 programs, for a total of 64 programs). These programs
may be selected via the switches in the programmer section on the front panel. The switches
marked BANK SELECT will step through the banks in order, and the two sets of eight switches
marked PROGRAM SELECT (numbered
1 through 8) allow immediate selection of a particular
program within
a bank. To choose a program for either the UPPER or LOWER polyphonic
synthesizer bank, step through the banks unt~lyou reach the bank you want, then hit the
PROGRAM SELECT switch for the exact program you wish. The selected bank will be indicated by
the digital display in the programmer section, and the selected program will be indicated both by
the digital display and by the LEDs embedded in the PROGRAM SELECT switches. You will be able
to see which program
is selected for both the UPPER and the LOWER synthesizer bank. The
PANEL select switches will allow you to choose which of these two programs you wish to have
displayed on (and connected to) the front panel patch controls.
Since the Prophet
is shipped with a full complement of 64 factory programs it will be ready to
play
as soon as it has been turned on and the initial tuning procedure has ended. For information
on these factory-loaded patches, see SECTION
7, THE FACTORY PRESET PROGRAMS. For
informationon MANUAL operation, see SECTION 3, THE PATCH CONTROLS.
1-5 PITCH AND MODWHEELS
The pitch wheel (PITCH) and modulation wheel (MOD) are located to the left of the upper
keyboard. Normally, both wheels affect
all voices simultaneously. The PITCH wheel has a center
detent position, from which the pitch may be varied up or down
by about a 5th. Both wheels can
be "disconnected" from the LOWER program by holding the LOWER TRANSPOSE DOWN switch
and hitting the LOWER TRANSPOSE UP switch. Repeating this procedure will re-connect the
wheels. This
is usefulwhen using the poly-sequencer.
The MOD wheel determines, for the most part, the amount of modulation to be routed via the
MON~MOD settings of a particular program. The total amount of modulation to be routed is
determined by the sum of the settings of: 1) the programmable LFO AMOUNT knob in the
MOW-MODsection on the front panel; 2) the MOD wheel; and 3) the voltage supplied from
PEDAL
1 (if it is programmed to affect the MONO-MOD section). Note that the MODwheel may
have different results on the upper and lower programs, since the MONO-MOD sections may be
programmed differently. For information on the effects that may be engaged via the MOD wheel
relative to the various factory-programmed patches, see the notes accompanying each patch
diagram inSECTION
7.
1-6 TRANSPOSE SWITCHES
These switches allow instant octave transposition of either UPPER or LOWER programs, within an
overall four-octave range. Each touch of the switch will raise or lower the program
by an octave.
The relationship between this overall range and the TRANSPOSE switches
is determined by the
settings of the FREQUENCY knobs in the oscillator sections of the front panel. These knobs also
have
a four-octave range; and if, for instance, both oscillators were set at the top of their
frequency range in
a particular program, the TRANSPOSE UP switch would have no effect (the
TRANSPOSE DOWN switch would in this case have
a four-octave range). In addition, the
TRANSPOSE switches always operate to the limit of the~rrange.
If you begin with a program that
has the osc~llatorstuned an octave apart, and continue to hit the TRANSPOSE UP switch, both
oscillators will end up in unison
at the top oftheir range.

The computer remembers the number ol times you strike a particular TRANSPOSE switch, even if
it has ceased to have an effect on the oscillators. Here is an example of what this means in actual
use: You begin with both oscillators set two octaves up (with their respective FREQUENCY knobs);
then you hit the TRANSPOSE UP switch five times. The
last three strokes will no longer transpose
the oscillators, but the computer
is still counting, so in order to transpose down again, you will
have to hit the TRANSPOSE DOWN switch three times before anything happens. On the fourth
stroke the oscillators will transpose down an octave.
If the KEYBOARD switch on OSCILLATOR B
is off, the TRANSPOSE will have no effect on that
oscillator. OSCILLATOR A will always be affected.
If the KEYBOARD switch in the FILTER section of the patch panel
is lit, the TRANSPOSE switches
will also connect to the CUTOFF FREQUENCY of the filtet. Since this c>aran,eterhas
a much
greater range than that of the oscillators
(10 octaves), successive strokes of the TRANSPOSE
switches may continue to alter the CUTOFF setting after the oscillators have reached the limit of
their range.
None ol the transpose operations performed with the TRANPOSE switches can be recorded
as part
of
a program. In order to change octaves permanently, you must adjust the FREQUENCY controls
on the oscillators (and perhaps the CUTOFF control on the filter).
To return quickly to the original programmed octave after transpositions via the TRANPOSE
switches, simply hit the PROGRAM switch for the program you are playing or change to
a new
program. (Adjusting either FREQUENCY knobs will also cancel the effects of the TRANSPOSE
switches.)
1-7 VOICE ASSIGNMENT
The assignment of voices to keys played onthe keyboard is done by the Prophet's computer. If the same
key
is struck repeatedly, the computer will continue toassign the same voice. If morethan five keys are
held down
at the same rime on either keyboard in NORMAL keyboard mode, the computer will
reassign the earliest usedvoices first; for example, playing C,
D, E, F, G, andA insuccessionand holding
all six keys downwill cause D, E, F, G, andA to besustained -the Cwill disappear when theA is played.
Inother words, the Prophet normally operateson
a "last-note priority" system: each new note played is
assigned to the earliest-used voice. In DOUBLE keyboard mode, reassignment will begin if more than
five
kys are held down (total) on both keyboards. In SINGLE and ALTERNATE keyboard modes
reassignment will occur if more than ten keys are held down on both keyboards.
There are two exceptions to this system. First,
if the UNISON switch is on, all five voices are assigned
to'a single key. UNISON assigns priority to the highest key held.This is particularly useful in DOUBLE
keyboard mode. (InUNISON mode. the keyboard operates in single trigger fashion: there will not
be
a new trigger unless there is a space between key depressions.)
The second exception to normal voice assignment is provided for the occasion when
a voice may
become"unplayable" duetocomponent failure. Insuch cases, a VOICE DEFEAT allows you to eliminate
the bad voice from the assignment system. The Prophet can then be played normally, with the
remainingvoices.The VOlCE ASSIGNMENT lights allow you to see which voice
is failing.
To defeat a voice, hold the key currently assigned to it with one hand while holdingUPPER PROGRAM
SELECT
1 and pressing UPPER PROGRAM SELECT 8 with the other hand. The voice will be defeated,
the corresponding light will go out, and the voice will remain defeated until the Prophet's power
is
switched off.

Defeating a voice inone synthesizer bank will also defeat the correspondingvoice inthe other bank.
For instance, defeating voice
4 in the UPPER synthesizer will also defeat voice 9 in the LOWER
synthesizer.
If power is turned olf, then on again - the voice will have to be defeated again (if it is still bad).
1-8 RETUNING
Although the computer tunes the oscillators when the Prophet is first turned on, it may become
necessarytoretune, particularly duringthefirst few minutes of operation since theoscillators needtime
tostabilize.After
20 minutes or so the instrument should not havetoberetuned very often, unlessthere
is a radicaltemperature change in the room.
Hitting the TUNE switch will tell the computer to retune the oscillators. When this
is done the front
panel will go dark
- except for the TUNE switch - for approximately 15 seconds, and then will return
to the previous front panel status.

SECTION 2
BASIC PROCEDURES
2-0 INTRODUCTION:THE FRONT PANEL
The Prophet-lo'sfront panelcontrols are color-coded to clarify the modesof operation and the funnion
of thecomputer's memory. All black knobs and switches are programmable; that is, their settings can be
recorded into memory and recalled in PRESET mode.
The silver knobs (MASTER VOLUME, BALANCE, and MASTER TUNE)and grey switches (PRESET, A-440,
TUNE, and TRANSPOSE switches, and the entire PROGRAMMER section) are not programmable. The
PITCHand MODwheels are also not programmable. The RECORDswitch
is orange, so that it caneasily
be distinguished.
All of the switchesexcept BANK SELECT and TRANSPOSE have LED indicators embedded inthem.And,
except for the two sets of
8 PROGRAM SELECTS, PANEL, KEYBOARD MODE, and TUNE, all LED
switches are alternate action: one push turns them on, the next push turns them off. For example, the
PRESET switch LED when lit indicates PRESET mode. The LED goes off when the Prophet
is switched to
MANUAL mode, by pushing the (lit)PRESET switch.
2-1 MODESOF OPERATION
In PRESET (PRESET switch LED lit) the Prophet-lo's synthesizers will be patched according to the
programs stored inthe locations indicated on the digital display. In this mode, entire patches can be
changed instantaneously using the BANK SELECT and PROGRAM SELECT switches in the programmer
section.
Inaddition to PRESET, the Prophet has MANUAL and RECORD modesofoperation. InMANUAL mode
a parch can be formed entirely "from scratch." RECORD
is a momentary modefor storingor relocating
programs. A"patch" becomes a"program" when recorded. Custom programscan therefore by created
h two ways: 1) by recording manually-formed patches or 2) recording edited programs. (Edited
programs can be recorded intothe original location
if the original program is not desired, or into a
new location.)
In MANUAL mode the control panel always indicates the status of the patch under construction. You
cansee exactly what signal pathsare closed by (lit)switches.The knobsettings reflect their actual values.
As you select different programs in PRESET the switch LEDs
still indicate how the switches are
programmed. Notethat the knobs cannot move with program changes, but stay where they were
last
set. So, in PRESET the knobs do not normally indicate their "current" setting. However as soon as you
move a knob to EDlT
a program, that knob converts to MANUAL operation. So only the knobs you
move will actually indicate their current setting: the parameters controlled by unmoved knobs do not
change.
This EDlT feature of PRESET mode
is a powerful tool that allows you to experiment with changes in
programs, uslng the patch controls. The original program remains unchanged and can be restored
at
any time by s~mplyhitting its PROGRAM SELECT again.

For example, supposeyou like program 3-3 but want to change OSC A pitch and prefer a brighter tone.
In PRESET mode, select BANK
3 - PROGRAM 3, adjust OSC A FREQUENCY to the desired pitch and
increasethe FILTER CUTOFF to the desired brightness. You can cancel any changes and return to the
original program by hitting PROGRAM SELECT
3. If you want to permanently change program 3-3 to
your edited version, record
it in 3-3. Or, if boththe original and edited versions are wanted, recordthe
edited program in
a new location.Remember that even though two programs (UPPER and LOWER)can
be selected
at a time, only the program indicated by the PANEL select switches can be altered via the
front panel patch controls. However, edited changes are remembered when the UPPER and LOWER
PANEL switches are hit. Hence, one can select UPPER and edit the UPPER program, and select LOWER
and edit the LOWER program independently
as desired. Both programs will play in their edited form,
even ifyou switch back and forth
a number of times.
NOTE
- If a particular patch is programmed with the RELEASE switch off bur with a pr,grammed
amplifier envelope RELEASE setting that will have an audible effect, this release can be engazed (while
in PRESET mode) by switching the RELEASE switch on, or using the footswitch. Further modifications
(non-permanent changes) to the preset programs can be brought about through the use of other
accessories which connect to the Prophet via jacks in the back panel. For information on these
possibilities, see SECTION 4 ACCESSORIES. Remember that the RELEASE switch and knobsettings may
be different on the upper and lower programs. Hence, the footswitch may have an effect on one
program and not the other depending on the different settings.
2-2 RECORDINGPROGRAMS
In general, to record a manually-formedpatch or edited program, the RECORD switch is pressed on,
then the desired destination BANK and PROGRAMare selected. NOTE
- To protect existing programs,
RECORD mode can only be entered
if the back panel RECORD ENABLE/DISABLE switch is up
(ENABLE).It
is suggested that the switch be left inthe DISABLE position until the modes of operation
and control tunctions are understood. This will prevent the accidental erasure of the factory preset
programs (Remember also that an accidental erasure
is not adisaster, since by referringto the diagrams
in SECTION
7 you can always patch a factory program manually, and re-record it).
The &act RECORD procedure is as follows:
1) Set the back panel RECORD ENABLE/DISABLE switch to the ENABLE (up)position
2) Switch on the orange RECORD switch inthe PROGRAMMER SECTION.
9j Select the desired general location (UPPER or LOWER) by using the PANEL select switches
4) Select the desired bank using the BANK SELECT. (Ignore this step
if current BANK is desired)
5) At this point you can abort RECORD mode by switching the RECORDswitch off.The memory will
not be affected.
6) Otherwise, pressingany PROGRAM SELECT will cause the patch or edited program to be recorded
at the correspondinglocationinthe selected bank. NOTE - Makesure to hit the correct PROGRAM
SELECT switch or you may erase a program you wanted to keep.
7) When a PROGRAM SELECT switch has been hit, the RECORD switch LED will automatically go off
and the Prophet will return to the mode it was in before recording.
8) After recording a patch it is always a good idea to return toPRESET modeand check that the program
-
is correctly recorded in the desired location.

To move a program from one location to another (editedor not),the procedure is as follows:
1) Select the program to be moved (set PANEL, BANK. PROGRAM)
2) Edit the program (if desired)
3) Hit RECORDswitch (latches up current program).
4) Change PANEL if necessary (lor moving from UPPER to LOWER or vice-versa)
5) Select destination BANK (if necessary)
6) Hit desi ed PROGRAhl SEL ICT
7) This new location now has the old programstored in it. In order to play the program, it is necessary
to hit the PROGRAM SELECT
a second time to "load" the program.
2-3
KEYBOARDMODESANDTHE UPPER/LOWER PANEL SWITCHES
The four programmable KEYBOARD MODE switches are an important part of the basic operation of
the Prophet-10, since they determine the relationship between the two 5-voice polyphonic synthesizers
and the two keyboard manuals.They offer agreat rangeof possibilitiesfor playing the programsstored
inthe Prophet's UPPER and LOWER program sections.
NORMAL Mode: The UPPER five voices (connected to the UPPER program) play on the upper
keyboard, while the LOWER five voices (connected to the LOWER program) play on the lower
keyboard.
SINGLE Mode: All ten voices will be assigned and will play their own UPPER or LOWER program.
Usuallythe UPPER and LOWER programs are set upto bethe same. The notes can be played oneither
keyboard inany combination.
DOUBLEMode: Hitting
a key (oneither keyboard)will engage one voice with the UPPER programand
one voice with the LOWER program. Only five keys can be played
at one time (since each key is
connected to bofh of the 5-voice synthesizer banks).
ALTERNATE Mode: Every new key hit will alternate between the UPPER and LOWER programs.
As can beseen, NORMAL
is the only modeinwhich it makes a differencewhich keyboard is physically
p?ayed. In the other three modes the keyboards can be used interchangably - together or separated.
So, these switches determine how the Prophet-10will be played. There
is also another factor insetting
upthe playing modeof the instrument: thechoiceof program beingdisplayed onthe front panel patch
controls. Since the KEYBOARD mode switches are programmable, their status
is recorded along with
each patch. At any given time, there will be two selected programs (UPPER and LOWER), but the
KEYBOARD mode operation will be determined only by the program that
is displayed on the front
panelpatch controls. Therefore, the UPPER/LOWER PANEL switches also play a roleindetermining the
playing configuration on the Prophet. For example, look at programs U-1-1 and L-1-1
- both are
patcheswith a brass sound.
If U-1-1 is displayed, the Prophet will operateinNORMALkeyboard mode,
but
if L-1-1 is displayed, the Prophet will operate in DOUBLEkeyboard mode.
These interrelations can be used to enhance the flexibility of the Prophet-10
as a live performance
instrument.

SECTION 3
THE PATCH CONTROLS
3-0 INTRODUCTION: THE FRONT PANEL
This section explains the functions of the ~atchcontrols comprising the "modules" (e.g. VCO, LFO,
VCF, and VCA)outlined on the front panel. The alternativesof each switch and rangesof each knob are
described relative to the overall signal flow of the voices and to the modulation circuitry.
In SECTION
1 and SECTION 2, we described the basic operation of the Prophet using the factory
programs accessible through the UPPER and LOWER PROGRAMMER.
It is true that the Prophet can
be used exclusively in PRESET mode, in which case the voice and modulation patch controls would
not be used very often. However
it is also true that using the instrument in this way would defeat a
large part of its overall purpose, which is to allow synthesists tocreate and record their own programs
for immediate use. The creationof satisfyingcustom programs depends entirely on your familiarity with
the controls.
By the way, in describing the controls this section will not attempt to be
a manual of synthesis
technique. However by referring tothe parch diagrams inSECTION
7 while playingthrough the factory
programs, you will soon grasp some of the sonic possibilities the Prophet makes available.As explained
inSECTION
7, we particularly encourage you to EDIT the factory programs (seeparagraph 2-1, MODES
Qf OPERATION).This is the best way to gain familiarity with the patchcontrols.
For more information on synthesis technique, refer ro the books and magazines listed in SECTION
6.
3-1 VOICE SIGNAL FLOW
The Prophet's audio output results from several stages of signal generation, combination, and
modification. The front panel
is divided into VOICE and MODULATION sections. (MODULATION
controls are covered in paragraph 3-01. It should be kept in mind that although only one voice
is
depicted on the panel, the voice controls simultaneously patch five voices in parallel. The figure
diagrams signal flow in
a single voice. Basically, the MIXER sets OSCILLATOR (VCO)A, B and NOISE
levelssent tothe FILTER (VCF)and AMPLIFIER (VCA)where, roughly speaking,the timbre and dynamics
are shaped. The EQUALIZER section further modifies the frequency spectrum. Then the voices of each
5-voice synthesizer bank are combined and their overall level and tuning are set by the VOLUME and
TUNE controls. Finally the two synthesizer banksare combined, and the instrument's overall level and
tuning are set by the MASTER VOLUME, BALANCE,and MASTER TUNE controls.

3-2 OSCILLATOR A
FREQUENCY knob: Controls pitch (oscillator tuning). Stepped (quantized) in semitones over
a
four-octave range. (Exact pitch is set with the MASTER TdNE knob.)
NOTE:
-0SC A pitch is always under keyboard control.
SAWTOOTHWAVESHAPE
switch: When on, asawtooth wave (containing all the harmonics) is supplied
as OSC A's output.
PULSEWAVESHAPE
switch: When on, a pulse wave is supplied as OSC A's output. Harmoniccontent is
dependent onthe setting of the PULSE WIDTH knob.
NOTES:
-When boththe sawtooth and pulse switches are on, sawtooth and pulsewaves are mixed at full level
(
-
and supplied as OSC A's output.
-When neither waveshape switch
is on, nosignal is supplied as OSC A's output.
PULSEWIDTHknob: Sets OSC A pulse width from approximately 1% to 99%. (Variesharmonic content
of pulse output.)
NOTES:
-The extreme settings of this knob (0 and 10) may cause the OSC A signal to degenerate to DC,
resulting in no output signal (of course, this knob will only have this effect if the pulse waveshape
.
IS selected).
-An exact square wave (having only odd harmonics) may be obtained by setting this knob to
approximately
5 and adjusting by ear for the drop out of the 2nd harmonic (theoctave).
SYNC
switch: when on, OSC A becomes"hard" synchronized to OSC B, and will therefore tune only
to harmonic frequencies of OSC B. Intermediate frequency settings will produce unusual waveforms
(andtherefore unusual timbres) at the next lower harmonicof OSC B.To gain an understanding of the
effect of SYNCing, check the following factory preset programs: 1-4,1-7,3-2, and U-4-3.
NOTES:
-When
a pulse shape with a wide pulsewidth is selected for OSC A insync with OSC B, and if OSC B's
frequency
is set much higher than that of OSC A, the signal from OSC A may degenerate into
DC since the pulse
is not given a chance to discharge before being re-synced.

3-3 OSCILLATOR B
FREQUENCY knob: Controls pitch (oscillator tuning). Stepped (quantized) in semitones over a four
octave range.
(Exaa pitch is set with the MASTER TUNE knob.)
NOTE:
-If the KEYBOARD switch
is off, the FREQUENCY knob will have a range of nineoctaves.
FlNE knob: Continuously varies pitch over a semitone range (up from the basic pitch setting of the
FREQUENCY knob).This knob is useful for detuning of OSC Brelative toOSC A. When nodetuning
is
desired, the FlNE knob should be set at 0.
SAWTOOTH WAVESHAPE switch: When on, a sawtooth wave (containing all harmonics) is supplied
as OSC B's output.
TRIANGLE WAVESHAPEswitch: When on,
a triangle wave (containing only odd harmonics) is supplied
as OSC B's output.
PULSE WAVESHAPE switch: When on,
a pulse wave is supplied as OSC B's output (harmonic content is
dependent onthe setting of the PULSE WIDTH knob).
NOTES:
- Wkntwo or three of the waveshape switches are on, the selected waveshapes are mixed at full level
and supplied
as OSC 0's output.
- When nowaveshapeswitch is on, no signal is supplied as OSC B's output. However,theoverall pitch
range of
a particular patch may still be determined by the FREQUENCY knob retting of OSC 0, if
OSC A is inSYNC with it.
POLSEWIDTH knob: Sets OSC Bpulse width from approximately 1%to 99%. (Variesharmonic content
of pulse output.)
NOTES:
-The extreme settings of this knob
(0 and 10) may cause the OSC B signal to degenerate to DC,
resulting in no output signal (of course, this knob will only have this effect if the pulse waveshape
is selected).
-An exact square wave (having only odd harmonics) may be obtained by setting this knob to
approximately
5 and adjusting by ear for the drop out of the 2nd harmonic (theoctave).
LO FREQUENCY switch: When on (with the KEYBOARD switch off), OSC B will function as a low
frequency oscillator (LFO), ranging from approximately
.4 Hz (or2.5 seconds-per-cycle) into low audio
frequencies. This function
is usually used in conjunction with the POLY-MOD section (see
paragraph
3-8).

KEYBOARD switch: When on, the frequency of OSC B is controlled by the keyboard. When off, the
frequency of
OSC B will not be controlled by the keyboard.
NOTES:
- If the KEYBOARDswitch is offand the LO FREQ switch is off, OSC Bwill act as adrone in the audio
range. Set the pitch of this drone with the FREQUENCY knobafter the KEYBOARD switch
is turned
off (otherwise you may have to retune).
-The use of OSC
I3 as a modulation source for the POLY-MOD will be discussed in paragraphj-8.
Normally,when OSC B is beingused as an audio signal source, the LO FREQ switch will beoffand the
KEYBOARDswitch will be
on.tfo4*Eep-eawkalmm-&iag~ams-
/e~a~~ec4oaded-kban!c?)-
3-4 MIXER
OSC
A knob: Determines the amount of OSC A's output sent to the filter
OSCB knob: Determinesthe amount of OSC B's output sent to the f~lter.
NOISE knob: Determines the amount ofwhite noise (combinationofall frequencies) sent to the filter.
.
NOTES:
-These mixer amount knobs are also used to program overall volume of the patch so that when
switching from one program to another in PRESET mode one program won't be wildly different in
volume than the others.

CUTOFF knob: The Prophet's filters are 4-pole, 24 dB-per-octave low-pass filters and therefore the
cutoff knob sets the frequency below which all elements of the signal are let through. The higher
frequency componentsof the signal (i.e. the frequencies above the cutoff frequency) are suppressed.
The higher the knob
is set, the more frequencies are allowed through the filter. Ingeneral terms, the
CUTOFF knob may be thought of as a tone control.
RESONANCE knob: As the setting of this knob is increased from 0 toapproximately 7, the amount of
resonance ("emphasis", "regeneration", or
"Q") applied to those signal frequencies at the cutoff
frequency will increase
(as the resonance increases,the frequencies far below thecutoff frequency will
be less audible relativeto the frequencies beingresonated).Ifthe setting
is increased beyond 7, the filter
will break into oscillation and will act
as a sine wave audio source whose pitch is determined by the
cutoff frequency.
ENVELOPE AMOUNT knob: The filter cutoff frequency may be contoured (shaped)electronically in a
patterndetermined by the settingsof the AnACK, DECAY, SUSTAIN.and RELEASE knobs (theseare the
controls for the ADSR envelope generator that
is connected tothe filter). The envelope amount knob
determines the amount (but not the shape) of this contouring that
is applied to the filter's cutoff
frequ&cy.
NOTES onthe ENVELOPE GENERATORS:
-The ADSR envelope generators whose controls appear
as the AnACK, DECAY, SUSTAIN, and
RELEASE knobs in the filter and amplifier senions generate voltage patterns
that can be used to
.contour timbre (via the filter's cutoff frequency) and loudness (via the VCA, see paragraph 3-6)
respectively. The voltage patterns generated have four stages (onefor each knob) as illustrated. The
entire contour pattern
is initiated when a key is depressed and proceeds through the attack and
decay stages
at rates determined by the settings of those knobs. The sustain level is determined by
the setting of the SUSTAINknob, and
is maintained as long as the key is helddown. When the key is
released the release stage is activated and proceedsat a rate determined by that knob.
-In the FILTER section, the ENVELOPE AMOUNT knob functions as an attenuator on the voltage
patterns from the filter's envelope generator. There
is nocomparable attenuator connected to the
VCA's envelope generator.

ENVELOPE
AMOUNT
(FILTER ONLY1
TIME
.
.I :-8
ATTACK TIME : DECAY TIME
: RELEA~E
TlME
-I
LENGTH OF TlME THAT KEY IS HELD DOWN
AlTACK knob: Determines the length of time it takes the envelope generator's contour to go from
0 level (at initial key depression) to maximum level.
DECAY knob: Determines the length of time it takes the envelope generator's contour to go from
maximum level to sustain level.If SUSTAIN
is set at maximum then the DECAY knobsetting is irrelevant.
SUSTAIN knob: Determines the sustain level of the envelope generator's contour. Remember, this is
a level setting, not a time setting; the sustain time is determined by the key being held down.
RELEASE knob: Determines the length of time it takes the envelope generator's contour to drop from
the sustain level to
0 level after the key is released. If the key is released before the attack and decay
stages ofthe envelopeare complete.the RELEASE knobsetting will determine the length oftime for the
\ -
contour to drop fromits level at the time of key releaseto 0 level. If the sustain is set at 0 and the attack
and decay stages are complete (whilethe key
is still depressed) then the releasesetting is irrelevant.
NOTES:
-The time range on the ATTACK, DECAY, and RELEASE knobs is approximately 1 millisecond to 30
seconds. Since the response to the knob is exponential, the durations as set on these knobswill not
be linear; for example, setting
5 on these knobs gives a period of approximately 'h second.
-Remember that, for the FILTER only (not the VCA), the overall level of the envelope generator's
contour
is determined by the ENVELOPEAMOUNT knob. If the envelope amount is set at 9 then the
.
envelope will have noeffect on the filter's cutofffrequency.
KEYBOARD switch: When on, the control voltage from the keyboard will be applied to the filter's
cutoff frequency (just
as it is normally applied to the frequency of the oscillators).This patch maintains
the cutoff frequency at a constant level relative to the notes played on the keyboard, and therefore
creates
a consistency of tone color over the entire range ofthe keyboard.When this switch is off, notes
played higher onthe keyboard will have more of their overtones suppressed than notes played lower
on the keyboard; as a result, notes played in the higher register of the keyboard will be less bright
in tone color than those notes played in the lower register of the keyboard.
NOTES:
-If the filter RESONANCE
is set so that the filter is in oscillation (i.e,generating a sine wave), then
switchingthe KEYBOARDswitch onwill allow the frequencyofthis sine wave to becontrolled from
the keyboard. Unless
a complex effect is desired when playing the filter's sine wave in this way, the
envelope generator setting will normally be set
at 0; the ENVELOPE AMOUNT knob should also
be set
at zero in this case (inorder to maintain a steady responsefromvoice to voice).

3-6 AMPLIFIER
The AlTACK, DECAY, SUSTAIN, and RELEASE controls in the amplifier section determine the settings
for the ampliiier's ADSR envelope generator. For details on the function of these knobs, see the
"NOTES on the ENVELOPE GENERATOR" and the notes on the AnACK, DECAY, SUSTAIN, and
RELEASE knobs in paragraph
3-5.
3-7 EQUALIZATION
EOUaL12aTION
LOW HID "10"
.
LOW knob: provides cut/boost facil~tiesfor lower frequency signals.
MID
knob: provides cul/boost facilities for mid-,ange frequency signals
HIGH knob: provides cut/boost facilities for high frequency signals.