Wine Country 1016.1 Operation 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

(408)

265-2008

FAX

(4081

2666591

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@l981 by
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 to this

number in all correspondence with the factory.

Please return your warranty card!

Table of Contents

SECTION I GETTING 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 I BASIC OPERATION

1-0 INTRODUCTION

1-1

Play~ng the Dernonstrat~on Sequences

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 OF OPERATION

3-0 INTRODUCTION

3-1 Power-On

3-2 IDLE MODE
3-3 RECORD MODE
3-4

ln~t~allz~ng Sequencer Programs

3-5

Real-T~me Recording

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-Srep Event 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 two completely programmable polyphonic synthesizer banks, each having five
complete and individual synthesizer "voices." Although each voice

is

keyed independently,

all

five

voices in each polyphonic bank function from the same patch setting, and are therefore homophonous.

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 be used

at

any one time. One

is

the UPPER program, with one 5-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 (one wired to the VCF and one wired to the VCA) and

a

3-band equalizer (EQ). In addition,

there are routings (via the POLY-MOD section) that allow for oscillator

B and the filter envelope

generator

lo lunction as modulation sources which can be applied to the frequency or pulse-width of

oscillator A, or the filter frequency. Finally, each 5-voice synthesizer bank has a single LFO which can be

applied to

all

of

its

voices for various effects. The two LFOs (UPPER and LOWER) can also be combined

(summed) and applied to both polyphonic 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

patches

which 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 up the Prophet-10, simply plug the power cord into an 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

polyphonic synthesizer banks for stereo effects.

The fixture for the removable power cord also contains the main AC fuse, facilities for selecting

between

100,120,220, and 240 volts AC line levels, and an AC line filter. Prophet-10s shipped in the USA

will be set

at

120, those shipped to Europe will be set

at

220, and those shipped to Japan will be set 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

connected to the chassis of the

instrument. It

is

up to 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 on the 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 up a shock hazard between the

-

pieces of equipment. The amount of hum

is

dependent on where 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 the signal level to be acceptable. The further away from each other the plugs
are connected to AC, the more hum will occur. The quality of wiring in the wall and wall socket will also
affect the amount of hum,

Here

is

a

summary of recommended procedures to follow when setting up the Prophet-10:

1) Plug the Prophet into

a

three-prong cutlet. 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.

Sequential Circuits

is

nor responsible for any equipment failure due to incorrect ACconnections, and

is

not liable for any personal injury due to electrical shocks as a resulc of poor grounding.

1-2

TURN-ON AND INITIAL TUNING

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 pro­gramming 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 OUTPUT CONTROLS

The MASTER VOLUME knob

is

used to adjust the overall volume of the Prophet-lo's output.

The BALANCE knob

is

used to adjust the relative volume of the upper and lower synthesizer banks

The A40 switch 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 pro­grammable 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~ng either the A40 reference 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~l you 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

information on MANUAL operation, see SECTION 3, THE PATCH CONTROLS.

1-5

PITCH AND MOD WHEELS

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

useful when 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-MOD section 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 MOD wheel 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 in SECTION

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~r range.

If

you begin with a program that

has the

osc~llators tuned an octave apart, and continue to hit the TRANSPOSE UP switch, both

oscillators will end up in unison

at

the top of their 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,eter has 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 on the keyboard

is

done by the Prophet's computer. If the same

key

is

struck repeatedly, the computer will continue to assign the same voice. If more than five keys are

held down

at

the same rime on either keyboard in NORMAL keyboard mode, the computer will

reassign the earliest used voices first; for example, playing C,

D,

E,

F,

G,

and A in succession and holding

all

six

keys down will cause

D,

E, F,

G,

and A to be sustained -the C will disappear when theA

is

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. 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. (In UNISON 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" due to component failure. In such cases, a VOICE DEFEAT allows you to eliminate
the bad voice from the assignment system. The Prophet can then be played normally, with the

remaining voices. 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 holding UPPER 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 in one synthesizer bank will also defeat the corresponding voice in the 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

necessary

to retune, particularly during the first few minutes of operation since the oscillators need time

to stabilize. After

20

minutes or so the instrument should not have to be retuned very often, unless there

is a radical temperature 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's front panel controls are color-coded to clarify the modes of operation and the funnion
of the computer'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

PITCH and MOD wheels are also not programmable. The RECORD switch

is

orange, so that

it

can easily

be distinguished.

All of the switches except BANK SELECT and TRANSPOSE have LED indicators embedded in them. 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

MODES OF OPERATION

In PRESET (PRESET switch LED

lit)

the Prophet-lo's synthesizers will be patched according to the

programs stored in the 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.

In addition to PRESET, the Prophet has MANUAL and RECORD modes of operation. In MANUAL mode

a parch can be formed entirely "from scratch." RECORD

is

a

momentary mode for storing or relocating

programs. A "patch" becomes a "program" when recorded. Custom programs can therefore by created

h

two ways:

1)

by recording manually-formed patches or

2)

recording edited programs. (Edited

programs can be recorded into the 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
can see exactly what signal paths are closed by (lit) switches. The knob settings reflect their actual values.
As you select different programs in PRESET the switch

LEDs

still

indicate how the switches are

programmed. Note that 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~mply hitting

its

PROGRAM SELECT again.

For example, suppose you 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
increase the 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

both the original and edited versions are wanted, record the

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 if you 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 knob settings 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

RECORDING PROGRAMS

In general, to record a manually-formed patch or edited program, the RECORD switch

is

pressed on,

then the desired destination BANK and PROGRAM are 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 in the 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 a disaster, since by referring to 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 in the 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 RECORD switch off. The memory will
not be affected.

6)

Otherwise, pressing any PROGRAM SELECT will cause the patch or edited program to be recorded

at

the corresponding location in the selected bank. NOTE - Make sure 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 to PRESET mode and check that the program

-

is

correctly recorded in the desired location.

To move a program from one location to another (edited or 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 RECORD switch (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 program stored 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

KEYBOARD MODES AND THE 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 a great range of possibilitiesfor playing the programsstored

in the 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.
Usually the UPPER and LOWER programs are set up to be the

same. The notes can be played on either

keyboard in any combination.

DOUBLE Mode: Hitting

a

key (on either keyboard) will engage one voice with the UPPER program and

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 be seen, NORMAL

is

the only mode in which

it

makes a difference which 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-10 will be played. There

is

also another factor in setting

up the playing

modeof the instrument: thechoiceof program being displayed on the 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

panel patch controls. Therefore, the

UPPER/LOWER PANEL switches also play a role in determining the

playing configuration on the Prophet. For example, look at programs

U-1-1 and L-1-1 - both are

patches

with a brass sound.

If

U-1-1

is

displayed, the Prophet will operate in NORMAL keyboard mode,

but

if

L-1-1

is

displayed, the Prophet will operate in DOUBLE keyboard 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

~atch controls comprising the "modules" (e.g. VCO, LFO,
VCF, and VCA) outlined on the front panel. The alternatives of each switch and ranges of 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 to create and record their own programs
for immediate use. The creation of satisfying custom 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 to the parch diagrams in SECTION

7

while playing through the factory
programs, you will soon grasp some of the sonic possibilities the Prophet makes available. As explained
in SECTION

7,

we particularly encourage you to EDIT the factory programs (see paragraph

2-1,

MODES

Qf

OPERATION). This

is

the best way to gain familiarity with the patch controls.

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

levels sent to the 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 banks are 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.

SAWTOOTH WAVESHAPE

switch:

When on, a sawtooth wave (containing

all

the harmonics)

is

supplied

as

OSC A's output.

PULSE WAVESHAPE

switch:

When on, a pulse wave

is

supplied

as

OSC A's output. Harmoniccontent

is

dependent on the setting of the PULSE WIDTH knob.

NOTES:

-When both the sawtooth and pulse switches are on, sawtooth and pulse waves are mixed at full level

(

-

and supplied

as

OSC A's output.

-When neither waveshape switch

is

on, no signal

is

supplied as OSC A's output.

PULSEWIDTH knob: Sets OSC A pulse width from approximately 1% to

99%.

(Varies harmonic 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 (the octave).

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

(and therefore 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 pulse width

is

selected for OSC A in sync 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 nine octaves.

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 B relative to OSC A. When no detuning

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 WAVESHAPE switch: 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 on the setting of the PULSE WIDTH knob).

NOTES:

-

Wkn two or three of the waveshape switches are on, the selected waveshapes are mixed

at

full level

and supplied

as

OSC 0's output.

-

When no waveshape switch

is

on, no signal is supplied

as

OSC B's output. However, the overall pitch

range of

a

particular patch may

still

be determined by the FREQUENCY knob retting of OSC 0,

if

OSC

A

is

in SYNC with

it.

POLSE WIDTH knob: Sets OSC B pulse width from approximately 1% to

99%.

(Varies harmonic 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 (the octave).

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 (or 2.5 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 KEYBOARD switch

is

off and the LO FREQ switch

is

off, OSC B will act

as

a drone in the audio

range. Set the pitch of this drone with the FREQUENCY knob after 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

being used

as

an audio signal source, the LO FREQ switch will be off and the

KEYBOARD switch 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

OSC B

knob:

Determines the amount of OSC B's output sent to the f~lter.

NOISE

knob:

Determines the amount of white noise (combination of all 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 components of 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. In general terms, the

CUTOFF knob may be thought of as a tone control.

RESONANCE knob:

As the setting of this knob

is

increased from 0 to approximately

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 the cutoff frequency will

be less audible relative to

the frequencies being resonated). If the 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

pattern determined by the settings of the AnACK, DECAY, SUSTAIN. and RELEASE knobs (these are the
controls for the ADSR envelope generator that

is

connected to the 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 on the 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 (one for 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 SUSTAIN knob, and

is

maintained

as

long

as

the key

is

held down. When the key

is

released the release stage

is

activated and proceeds at 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

no comparable 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 knob setting

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 of the envelope are complete. the RELEASE knob setting will determine the length of time for the

\

-

contour to drop from its level

at

the time of key release to 0 level. If the sustain

is

set

at

0

and the attack

and decay stages are complete (while the key

is

still

depressed) then the release setting

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 knobs will 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 ENVELOPE AMOUNT knob.

If

the envelope amount

is

set at 9 then the

.

envelope will have no effect on the filter's cutoff frequency.

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 of the keyboard. When this switch

is

off, notes
played higher on the 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
switching the KEYBOARD switch on will allow the frequency of this sine wave to be controlled 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 (in order to maintain a steady response from voice 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~ties for lower frequency signals.

MID

knob:

provides cul/boost facilities for mid-,ange frequency signals

HIGH

knob:

provides cut/boost facilities for high frequency signals.

3-8

MODULATION

The Prophet provides two distinct modulation systems, MONOphonic-MOD and POLYphonic MOD.
Modulation involves a source and

a

destination; the destination

is

modulated (changed) in a pattern
determined by the source. The MONO-MOD system, diagrammed above, uses a low-frequency
oscillator (LFO) with sawtooth, triangle, and square waves

as

source material. Note that the UPPER

synthesizer bank provides

a

descending sawtooth wave

as

a modulation source, while the LOWER
synthesizer bank has an ascending sawtooth wave. These modulation sources can be routed to the
frequency and pulse-width of OSC

A

(FREQ

A,

PW

A),

the frequency and pulse-width of OSC B (FREQ

6,

PW

B),

the filter's cutoff frequency (FILTER), or any combination thereof.

The amount of modulation directed to these destinations

is

determined by the programmable LFO

AMOUNT knob, the non-programmable MOD wheel, and PEDAL

1

(if

it

is

programmed to control
MONO-MOD). The amounts from these three sources are summed, determining the total amount of
modulation. The FREQUENCY knob in the LFO section determines the LFO frequency (or rate), the
overall range being approximately

.04

Hz (or

25

seconds-per-cycle) to

20

Hz. The SHAPE switches
determine the waveforms used as the LFO portion of the modulation source. (When more than one
waveshape switch

1s

on, the selected waveshapes are mixed at full level.)

The UP-LOW MIX switches allows the UPPER LFO and the LOWER LFO to be

m~xed

(at

full level) and

applied to both the UPPER and LOWER program selected. This

is

useful for performing "double

modulation" effects.

If

you wish to apply one LFO to both UPPER and LOWER, simply program one LFO

as desired, program nothing on the other

LFO (all shape switches off) and program UP-LOW MIX on.

This

is

useful when synchronized modulation

is

desired on both UPPER and LOWER programs.

In the-prophet's unique POLY-MOD section, five LFOs (OSC Bin LO FREQ mode) or five filter envelope

generators-one from each of the five voices in either polyphonic synthesizer bank-can be used

as

modulation sources (see above). Although the modulation routing will be the same for each voice, the
minute differences between the voices (the phase relationships of the oscillators, for instance) will

create modulation effects that will be slightly different from voice to voice and from note to note. This

is

in direct contrast to the WHEEL-MOD section where, since a single modulation source

is

applied

e7pally to all five voices, the modulation effect

is

exactly the same from note to note.

As said above, OSC B and

the filter envelope generator are the possible sources for modulation in the

POLY-MOD section. The amounts of each source are determined by the SOURCE AMOUNT knobs.

The possible destinations are frequency of OSC A (FREQ A), pulse-width of OSC A (PW A), and the

filter's cutoff frequency (FILTER). There will be no modulation via the POLY-MOD section if the
SOURCE AMOUNT knobs are set

at

0

or

if

all destination switches are off.

POLY-MOD with OSC B

as

source

is

useful for creating clangorous sounds such

as

bells, chimes,
percussive sounds, and "ring modulation" type sounds. Various pitch and timbre sweeps may be
obtained using the filter's envelope generator

as

source. The LO FREQ switch on and/or KEYBOARD

switch

off settings in the OSC B module are primarily for use when OSC B

is

used

as

a POLY-MOD

source rather than

a

signal source.

In order to get an idea of some of the modulation possibilities offered by the POLY-MOD section of the
Prophet, study

its

use in some of the factory preset programs.

3-9

MISCELLANEOUS

RELEASE switch: When off, the amplifier and filter release times are approximately

0

(instant release).

(Actually, the release time

is

set at about 2 when the RELEASE switch

is

off, so there won't be an audible

"whack" when the key

is

released - which would be caused

by

the instantaneous closing down

of the VCA).

NOTES:

-This switch must be off to allow for the operation of the RELEASE footswitch (see SECTION

4

ACCESSORIES).

-Remember that this switch

is

separately programmable for UPPER and LOWER programs, €fen

though only one setting

is

visible. This

is

important relative to the use of the RELEASE footswitch.

DRONE switch: When on, the amplifiers on

all

voices (within the programmed synthesizer bank) will

stay

on for continuous sound once they are engaged via the keyboard.

If

the SUSTAIN in the AMPLIFIER

section

is

set to zero, you will not get a drone effect.

UNISON switch: When on, the Prophet will assign

all

five voices (within the programmed synthesizer

bank) to the highest played note. In other words, in UNISON mode the Prophet becomes

a

very

"fat"

monophonic synthesizer.

GLIDE knob: Effective only in UNISON mode, this knob

determines

the rate of gl~de (portamento)

between notes played on the keyboard.

NOTES:

-Remember that these controls are programmed separately for the UPPER and LOWER synthesizer
banks. Only one program status will be visible, but both will be operative.

-

In UNISON mode the svnthesizer bank will function on a hiah-note prioritv svstem. This

is

useful for

DOUBLE mode

lead-li~e-plus-chord effects. (UPPER

in

UNISON:

LOWER

program not in

UNTSON).

TUNEknob: For detuning one synthesizer bank relative to the other; will vary pitch continuously over

a

semitone range (up from the basic pitch setting of the oscillators].

If

no detl~ning

is

desired, the TUNE

knob should always be set

at

0.

VBLUME knob: For setting the overall level of programs relative to one another within one synthesizer

bank. This will allow for equal volume levels from program to program within

a

given series

of programs.

NOTES:

-If the MIXER, EQUALIZATION, and VOLUME knobs are all set

at

full level, the synthesizer may
distort. There are many levels of volume control on the Prophet-10, and they should be used
judiciously.

PEDAL

1

&

PEDAL

2:

These programmable switches allow for the routing of two external control

volrages to various destinations, (The Prophet-10

is

shipped with two pedals for this purpose, but other

voltage sources may be used

as

well; see SECTION

4,

ACCESSORIES.) PEDAL 1 may be routed to the

FREQUENCY of OSC A (FREQ A), the FREQUENCY of OSC

B

(FREQ

B),

the CUTOFF frequency of the

filter (FILTER), the VCAs (AMP). the MONO-MOD section, or any combination of the above. PEDAL

2

may be routed to the CUTOFF frequency of the filter (FILTER, the VCAs (AMP), or both. The amount of
voltage applied to these sources will be determined by the position of the pedal (or by the

outpur of any

other control-voltage device used).

NOTES:

-Remember once again that the routings for these pedals can be different for the UPPER program and
the LOWER

prlgram: the sar,ie pedal could have an entirely different function, depending on which

keyboard man

~al

you play (and on which keyboard mode you are on). Only one routing will be

displayed, but both the UPPER and LOWER routing will be functional.

-

If you do not plan to connect the pedals to the Prophet-10, it

is

best to program

all

of these switches

off.

If rhe AMP switch

is

engaged for either pedal and no pedal

is

plugged in, the VCAs for (hat

rynthesizer bank will remain closed and no sound will come from (he insrrument.

SECTION

4

ACCESSORIES

AND THE BACK PANEL

44

INTRODUCTION

The Prophet-10

is

shipped from the factory with two foot pedals and two foot switches,

all

of which can
be connected to the instrument via the back panel to provide many different kinds of nuance control
over the output of the synthesizer

bank5 Other interface capabilities are also provided, which may be

used

if

desired to create even more external control.

4-1

CONTROL VOLTAGE IN - PEDALS 1 AND

2

The two voltage pedals shipped with the Prophet are connected to

ir

via the two

'A"

jacks labeled CV IN.

The routings of these two pedals are determined by the programmable switches on the front panel

labeled PEDAL 1 and PEDAL

2

(see SECTION 3, paragraph 3-9). These voltage pedals are the most

common devices for use in this context, but various other devices (such as

a

ribbon controller, and

x/y

joystick controller, or a sample-and-hold module) will also provide for control of various interesting
effects. All voices within

a

given synthesizer bank will be affected equally by the input voltages. Note

that these inputs are

nor calibrated

at

1 v/octave.

The

'2

jack labeled RELEASE allows for footswitch control of the release portion of the filter and

amplifier envelope generators.

It

functions in much the same manner

as

the RELEASE switch on the

front panel. and is only operative when the RELEASE switch

is

off. It then takes the place of the RELEASE

switch: when pushed, the programmed amplifier release time

is

engaged; when not pushed, the

programmed amplifier release time

is

not engaged. In that respect,

ir

is

similar to a piano sustain pedal.

The footswitch for use in this context comes standard with every Prophet-10.

.

The

'A"

jack labeled PROGRAM INCREMENT can be used to step through the programs in a particular
program bank (both UPPER dnd LOWER) while both hands are engaged in other performance activities.
Each time the footswitch

is

depressed, both the UPPER and LOWER programs will increment one
position. This will most often be used to increment from one set of conceptually-linked programs to
another

(e.g., U-1-1 and L-1-1 would increment to U-1-2 and L-1-2), but the increment switch will work

on both program banks regardless of their relative position

(e.g., U-1-3 and L-2-4 would increment to

U-1-4 and L-2-5).

If

the currently selected program

is

an

8,

the increment footswitch will cycle back to 1

(U-1-8 would increment to U-1-1). The increment footswitch will never change banks;

it

will only cycle

through

the eight programs of the selected bank (for both UPPER and LOWER programs). The

footswitch for use in this context comes standard with every Prophet-10.

The

?4"jack labeled SEQUENCER

is

for use in connection with the optional POLYPHONIC SEQUENCER.

It serves the same function

as

the STOP/CONTINUE switch on the sequencer's front panel. Its function

will be described in SECTION

5

POLYPHONIC SEQUENCER.

4-3

MONOPHONIC SEQUENCER INTERFACE

i

The four1/." jacks in the SEQUENCER section of

the

back panel (VOLTAGE IN. GATE IN, VOLTAGE OUT,

-

GATE OUT) are provided to allow for the interfacing of a Sequential Circuits Model 800 digital
sequencer to the Prophet-10. The Prophet, when connected to

a

Model 800, devotes voice 5 of the

UPPER synthesizer bank to the sequencer; the other four voices of the UPPER synthesizer can be played

"live" while the sequencer is controlling voice

5.

NOTE: When a Model 800

IS

connected ro

a

Prophet-10 and

is

therelore controlling voice

5,

the corresponding voice on the LOWCR synthesizer,

voice

10,

will bedisabled Even

if

the keyboard

is

in DOUBLE mode, the sequencer will only play voice

5

-voice 10 will be disabled whenever the Model 800

is

connected to the Prophet-10.

The diagram below shows how the Model 800 should be connected to the Prophet-10. The Model 800
TRIGGER IN and VOLTAGE IN switches should be in the up (1) position; the TRIGGER OUT switch
should be in the

renter

(2)

positi(8n. When reccrdint; a sequence, the Prophet-10 will send each note

played to the sequencer, together with

a

trigger; when playing back a sequence, the Prophet will route

all

input control voltages and gates to the same voice (voice

5).

Trigger In Trigger Out

Voltage

In

1

Voltage Out

SEQUENCER SYNTHESIZER

Trigger Out

4--

--

Gate In

-

Voltage Out

4

C

Voltage In

Thqe four jacks can also be used for other functions: the OUT jacks can be used to control other
synthesizers (most common 1-volt-per-octave synthesizers), while the IN jacks can be used to apply
other controllers (such

as

analog sequencers, sample-and-hold units, guitar synthesizer pitch followers.

etc.) to voice

5

of the Prophet. However, slnce VOLTAGE IN

is

"digitized"

by

the microcomputer to

maintain tuning with the other voices, the external controller will not be able to "glide." Also, the

voltage will only be converted on

a

new gate edge. Both VOLTAGE jacks are exactly 1-volt-per-octave.

The GATE OUT

is

a

+15 volt gate, and GATE IN can be any signal which switches through

at

least

3.5

volts.

NOTE: Any time

a

plug

is

inserted into the GATE IN jack on the Prophet-10, the computer disconnects

voice

5

and voice 10 from the keyboards; the instrument becomes essentially two 4-voice synthesizers,

with voice

5

reserved for the external input (if any) and voice 10 disabled. The monophonic sequencer

interface cannot operate

if

voice 5 or voice 10 has been disabled (see paragraph 7-71.

POLYPHONIC SEQUENCER OPERATION MANUAL

SUBSECTlON 1

BASIC OPERATION

1-0 INTRODUCTION

The Model

1015 Polyphonic Sequencer within the Prophet-10 uses the storage capabili-

ties of

a

second microcomputer system to allow you to directly record and edit your
own instrumentals. It allows ten-voice polyphony, a 2600-note capacity, wide range of
playback speed and of transposition, "multi-track" editing, operation in either Real­Time or Single-Step modes, recordable

synthesiz-r program selections, and permanent

storage of sequences and synthesizer programs on digital cassettes.

You probably already know that when you play the Prophet-10, you are actually
providing "data" to a microcomputer which in turn controls the synthesizer voices. The

basic idea of

real-t~me sequencing is fairly simple. Basically, the Sequencer contains

a

clock, microprocessor, and memory. The clock generates 50 to 500 pulses per second

(Hz) as adjusted by the SPEED knob. To record, every time

a

clock pulse occurs the
microprocessor obtains from the Prophet-10 data signifying what keys are being held on
the Lower keyboard. By comparing each keyboard "sample," the microprocessor
discovers what keys are going on and off. It records in memory the number of the clock
pulse (or, step) at which each event

(a

note going on, or

off,

or a program change)

occurs. For playback, the microprocessor counts elapsed clock pulses and brings each

1

event out of memory as the clock count matches the sequence step numbers. The
microprocessor converts each event from memory into the same type

of

keyboard
sample data which it received and sends it to back to the Prophet. The Prophet's
computer interprets this data just as

if

it were the original "live" data from its own

Lower keyboard.
The Polyphonic Sequencer, then, substitutes for the lower keyboard which is in turn

programmed by the Prophet-10's KEYBOARD MODE controls. If keyboard mode is

NORMAL, the Sequencer

will drive only the Lower five voices programmed by the
current Lower program. The Upper manual can then be used "live." If the mode is
SINGLE (and the Upper and Lower programs are identical), the Sequencer will be able
to play up to ten notes at once.

If

in DOUBLE mode, the Sequencer will simultaneously

drive both the Upper and Lower voices to the five-voice limit. In ALTERNATE mode,

the Sequencer

will alternately assign up to ten notes at once to the Upper and Lower

voices.
Unlike the Prophet, the Sequencer memory does not save its contents when power is

turned off. The digital cassette deck is used for permanently saving the data in the
Sequencer memory and for loading the memory with sequences when power

is

turned on.

It takes less than

a

minute to load a sequence cassette, during which time the Prophet

can be played normally.

This section contains instructions for basic operation. You can play the demonstration

sequences by following para.

I-I. The remainder of the section explains basic Real-

T~me recording, playback, and editing. Read also Sub-section 2, which discusses use

of

the digital cassette deck.