DOEPFER A-100 Series User manual

SYSTEM A - 100
Owner’s Manual
doepfer Musikelektronik Gmbh

EWarning:
Inside the A-100 power supply are dangerous vol-
tages. It is essential to take careful note of the
following safety instructions:
• Before opening up the case or moving a module or
blanking panel, always take the mains power
supply plug out. This applies equally to removing
or replacing any panel or module.
• All empty spaces in the rack must be filled with
blanking panels.
• Before use, the top and bottom covers must also be
properly fixed in place. If modules are permanently
fixed (eg. built into a 19” rack case) then the top of
the highest of the rack systems and the bottom of
the lowest must have their covers properly fitted.
The instrument must never be operated outdoors but
only in dry, closed rooms. Never use the instrument in
a humid or wet environment nor near inflammables.
AImportant safety notes.
Whenever electrical equipment is used, several
basic precautions need to be taken, including the
following:
• Before using any part of the instrument, read the
instructions and notes carefully.
• The instrument may only be used for the purpose
described in this operating manual. Due to safety
reasons, the instrument must never be used for
other purposes not described in this manual. If you
are not sure about the intended purpose of the
instrument please contact an expert.
• The instrument may only be operated with the
voltage written on the power input on the rear panel.
• Before opening the case disconnect the power plug.
• All eventual modifications must only be carried out
by a qualified person who will follow the valid safety
instructions. Every modification should becarried
out only at the manufacturer or an authorized ser-
vice company. Any modification not released by the
manufacturer leads to the extinction of the opera-
tion permission.
• The instrument must never be operated outdoors
but only in dry, closed rooms. Never use the instru-
Important safety notes System A - 100 doepfer
ii

ment in a humid or wet environment nor near
inflammables.
• Do not use this instrument in damp environments,
or close to water.
• No liquids or conducting materials must get into the
instrument. If this should happen the instrument
must be disconnected from power immediately and
be examined, cleaned and eventually be repaired
by a qualified person
• Do not use this instrument in close proximity to heat
sources such as radiators or ovens. Don’t leave it
in direct sunlight.
• This instrument must be assembled or installed in a
19” rack in a way that guarantees sufficient ventila-
tion and air circulation.
• The instrument must not be exposed to temperatu-
res above 50°C or below -10 °C. In use, the
instrument must be at a minimum temperature of
10 °C.
• Keep the top side of the instrument free in order to
guarantee proper ventilation, otherwise the instru-
ment could be overheated. Never place heavy ob-
jects on the instrument.
• This instrument can, without any external amplifica-
tion or in combination with a headphone or speaker
amplifier, produce sound levels which can damage
your hearing. Don’t work at high sound levels for
prolonged periods of time, and don’t ever use levels
which cause discomfort.
• The instrument’s mains power supply lead should
be disconnected if it is not used for any substantial
period. If there is any damage the cables must be
repaired or replaced by an authorized person
• Do not tread on the mains supply lead.
• In disconnecting the lead, pull the plug, not the
cable.
• If this instrument is connected to others, check in
their manuals for connection instructions.
• Make particularly sure that no object falls into the
instrument, and that no liquid gets into it.
• Transport the instrument carefully, never let it fall or
overturn. Make sure that during transport and in use
the instrument has a proper stand and does not fall,
slip or turn over because persons could be injured
• The instrument must be checked and serviced by a
qualified technician in the following cases:
a. the power supply lead or connector is damaged
in any way,
b. an object or fluid has somehow got into the
instrument,
c. the instrument was exposed to rain,
d. the instrument stops working properly or starts
to behave erratically,
e. the instrument is knocked over or dropped and/
or its case is damaged.
• As stated above, there are no user-serviceable
parts in the instrument. Refer all repairs to qualified
service personnel.
doepfer System A - 100 Important safety notes
iii

Contents System A - 100 doepfer
iv
Contents
Important safety notes .......................................... ii
Contents ................................................................. iv
About this manual ................................................... v
Introduction ............................................................ vi
1. Important notes .................................
1
1.1 Connecting to the electricity supply ........ 1
1.2 Installation .............................................. 1
1.3 Care and maintenance ........................... 1
2. Overall design ............................................ 3
2.1 Introduction ............................................ 3
2.2 Installing modules .................................. 4
2.3 Interconnecting modules ........................ 6
3. Signal flow in the A-100 ........................ 7
3.1 The principles of voltage control ............ 7
3.2 Signals in the A-100 ............................... 8
3.3 The System Bus in the A-100 ................ 9
3.4 Integrating the A-100 with MIDI ........... 11
4. A-100 BS Basic Systems .................... 13
5. Accessories .............................................. 15
6. Items included as standard ............... 17
7. Further reading ....................................... 19
8. Module overview ..................................... 21
9. Appendix .......................................... 29
9.1 Adding a 5 V power supply ................... 29
9.2 Installing the AD5 low-cost 5V adaptor 31
9.3 Using the Mini power supply/bus .......... 33
10. Using the modules
HBecause the A-100 is a modular system,
each module has its own separate manual,
which can be inserted into this ring-binder.

About this manual
This user manual describes the A-100 modular synthe-
sizer system, and explains how to use each section of
it.
If this is your first time using the A-100, please
make sure you are familiar with all the safety in-
structions (eg. pages ii - iv) and important notes
(chapter 1).
Because of the modular nature of the A-100, this
manual is also designed to be modular.
Chapter 2 (Overall design) describes the physical
make-up of the system - and particularly how to install
the individual modules into the 19” rack.
Chapter 3 (The A-100 signal flow) details the A-100’s
signal path: the basic principles of voltage control, how
to bring MIDI into the equation, and the possibilities for
voltage-controlled modulation.
Chapter 4 describes the A-100 Basic System.
Chapter 5 details accessories.
Chapter 6 explains the standard items included.
Chapter 7 suggests further reading.
Chapter 8 (Module overview) gives a run-down of the
individual modules presently available, and an idea of
their potential uses.
Chapter 9 (Appendix) deals with installing an extra 5V
power supply, for modules such as the A-190 and
A-191.
Detailed descriptions of the individual modules fol-
low, in self-contained chapters, with descriptions,
user examples, and patching aids. When buying indi-
vidual modules, the relevant manual chapters which
are included should be inserted into this ring binder.
In the manual, you’ll find various symbols used:
Aimportant user and safety advice
Hnote
➀ ... diagram numbering of module controls
 ... diagram numbering of module in / outputs
❒next step in a list of instructions
Ppractical hint or tip
doepfer System A - 100 About this manual
v

Introduction System A - 100 doepfer
vi
Introduction
In the A-100, Doepfer have produced a capable and
versatile analog modular synthesizer, built in the style
of the classic modular systems of the seventies.
The renaissance of analog synthesis in the last few
years shows that analog sound production has a vital
place alongside sampling and digital synthesis, and
can produce sounds that are unobtainable by any other
means. In addition to the unique sounds of its oscilla-
tors, filters, amplifiers, phasers, frequency shifters,
wave-modifiers, different control sources, and so on,
analog synthesis can provide almost unbounded mo-
dulation opportunities, conventional and unconventio-
nal - limited only by the number and variety of modules
available.
In designing the A-100, our priorities were: good sound
quality; ease of integration into a MIDI system; diversity
of modules available; and, maybe most important of
all, affordability.
Of course, a modular system doesn’t just have advan-
tages. Creative work with an audio construction kit like
this takes time and practice, especially to start with.
Anyone who wants to be able to check out all its
available sounds at the press of a button will be very
disappointed with a modular system. Each unique
sound has to be puzzled out, and may never be exactly
repeated.
Nor are there any fixed rules for connecting the various
modules. A modular is an open system, in which
practically anything is possible, and that’s where the
fun really starts. Diversity and experimentation - and
sometimes lateral thinking - are the keys to its power.
Although the user manuals for each module are very
comprehensive, they can’t substitute entirely for a ge-
neral overview and knowledge of analog synthesis.
Some very good specialised books have been written
on the subject, and although some may be out of print,
it’s crucial to find one or two of them, and learn from
them. With that, the whole world of modular systems
will open up to you, and you’ll suddenly appreciate their
fascination and sheer sonic power.
We hope your A-100 brings you serious pleasure!
July, 2009
doepfer musikelektronik gmbh

doepfer System A - 100 1. Important notes
1
1. Important information
AAs well as the important safety notice
(see ii - iii) please also read and take
note of the following points.
1.1 Connecting to the electricity supply
• The system A-100 must only be connected to the
mains voltage that is specified at the back of the
A-100 frame (220 V to 240 V / 50 Hz or 110 to 120
V / 60 Hz).
• If the fuse has to be replaced only the type of fuse
specified at the back of the A-100 frame is allowed.
If another fuse is used the warranty is void and the
A-100 may be damaged. The fuse is located at the
mains inlet on the back of the A-100 frame
(exception: suitcase version with mains inlet at the
front). To replace the fuse one has to disconnect
the mains cable and remove the fuse holder (e.g.
with the aid of a screw driver). The fuse holder is a
small black plastic part that is inserted into the
mains inlet.
• Do not connect the A-100 to a socket or outlet
which is also being used by equipment such as
electric motors, lighting dimmers, etc, which can
cause interference. Use a separate outlet for the
A-100.
1.2 Installation
• Do not expose the A-100 to rain or moisture.
• Operation is allowed only in a dry environment in a
closed room but not in the open country.
• The installation near a large amplifier or other
equipment which uses powerful mains transfor-
mers may cause hum.
• Do not install the A-100 in close proximity to equip-
ment which produces an electromagnetic field
(monitors, computers, etc.), to avoid the possibility
of mutual interference.
• Use in a dusty environment should be avoided.
1.3 Care and maintenance
• Apart from cleaning the instrument, no other user-
maintenance is recommended, of the modules or
system busses. Internal maintenance should be
carried out only by qualified technicians (see pages
ii - iii: "Important safety notice").
• For regular cleaning, use a soft, dry, or slightly
damp cloth. To remove dirt, if necessary, use a
cloth slightly moistened with a very diluted mild
detergent. This should be more than sufficient to
clean the instrument. Never use solvents like
petrol, alcohol, or thinners.

System A -100 doepfer
2
Fuse values for different mains voltages and power supplies
Type of power supply
Mains voltage
A-100NT12
(standard power supply, 650 mA output
current)
A-100PSU2
(power supply with ring core/toroid
transformer and 1.2A output current)
115V 250 mA time lag (slow blow) 630 - 800 mA time lag (slow blow)
230V 125 mA time lag (slow blow) 315 - 400 mA time lag (slow blow)

doepfer System A - 100 2. Overall design
3
2. Overall design
2.1 Introduction
The A-100 modular system is based on a standard 19”
rack system A-100 G into which individual Modules
can be fitted in any chosen layout.
The rack system (see Fig. 1) conforms to the 19”
standard, and consists of two sections each 3U high,
tied together by 6U side panels. It contains two system
busses (1), the internal power supply (2) , and the
main electrical supply socket (3).
Module front panels are all 3U high. Their width is
measured in HP (1 HP = 5.08 mm). The rack system
has a usable width of 84 HP (see Fig. 1). If the
modules you install don’t use up the entire 84 HP, then
you must cover up the spaces with blanking panels.
In each rack system there are two system bus bars
(one for each section), to each of which up to 14
modules can be connected, using ribbon cable. The
bus bar serves to supply power to the modules, and
also to send control voltages etc. to some of the
modules (see Chapter 3).
Fig. 1: A look inside the A-100 G rack system
The rack system power supply produces voltages of
+12 V and -12 V and can put out a maximum current
of 650 mA. In setting up a modular system, make sure
that the total current required by all the modules does-
n’t exceed this maximum. If it does, then a second
power supply (see Accessories) will need to be instal-
led (at position 4,Fig.1). As a rule, though, one
power supply should be sufficient for a rack system.
4
2
3 HU
84 HP
1
1
3

2. Overall design System A - 100 doepfer
4
2.2 Installing modules
AImportant:
Before you install a module into the rack
system:
DCalculate the total current requirement
of existing modules plus the new mo-
dule/s.
D
Checkthat this total is less than 1200mA.
DIf it is, the existing power supply is fine.
DBut if the total current requirement is
more than 1200 mA, you mustinstall a
second power supply (see Accessories)
before installing the module/s. Follow the
installation notes that come with the se-
cond power supply.
H Ignoring this warning can result in damage to
your system, and will void your guarantee!
Once you’ve checked that there is sufficient current in
reserve for the extra module/s, there’s nothing to stop
you going ahead and installing them. Read on!
D First of all, take the A-100’s plug out of the wall
socket.
D Plug the supplied ribbon cable into the module’s
bus socket (see 1in Fig. 2). As a rule, the cable is
16-way, but some modules only have a 10-way
cable. Look carefully at the cable, and then press
the appropriate connector onto the module’s bus
pins (see 2in Fig. 2).
ACheck very carefully that it is connected so
that the coloured marking on the ribbon
cable is at the bottom of the module’s
connector (see 3in Fig. 2), and that the
connection is perfect, and pushed fully
home, not at a slight angle. Failure to
check this may result in the module’s instant
destruction as soon as the power is turned
back on.

doepfer System A - 100 2. Overall design
5
Fig. 2: Connecting the ribbon cable to the module
D Now join the free end of the ribbon cable (see 2in
Fig. 3) to the nearest available position on the
system bus board (see 1in Fig. 3).
ACheck very carefully that it is connected so
that the coloured marking on the ribbon
cable is at the bottom of the bus connector
(see 3in Fig. 3), and it is pushed fully
home, not at a slight angle. Failure to
check this may result in the module’s instant
destruction as soon as the power is turned
back on!
Fig. 3: Connecting the ribbon cable to the bus
board.
H When you’re installing extra modules, it may
be necessary to take another module or two
out, to allow you easier access to the bus
board.
D Place the module carefully into the space in the
rack, and fasten it firmly in place with the supplied
screws. Put back any covers or blanking plates,
and screw them in firmly.
D Now plug the system A-100 back into the main
power supply, and switch it on.
D Test out the newly installed module.
If it doesn’t seem to be working as expected, im-
mediately disconnect the system from the power
supply again.
Bus Board

2. Overall design System A - 100 doepfer
6
In this case, double-check the connections, making
completely sure that the ribbon cable is the right
way round where it connects to the module and the
bus.
Once your system is assembled and operational, you
should make use of the the patch sheets which come
with each module.
Photocopy the patch sheets for each of your modules,
cut these out, and stick them onto a sheet of paper in
the order in which they occur in your system (see Fig.
4). Then photocopy this sheet, and use the copies to
note down good settings and patches.
2.3 Interconnecting modules
For connecting modules to each other, you need
mono mini-jack (∅
∅∅
∅3.5 mm) patch leads. You can
obtain patch leads from us (see Accessories in chap-
ter 5) in different lengths.
Fig. 4: Example of a personal patch sheet.
A-110
VCO
CV 1
CV 2
PW CV 1
Tune
CV 2
PW
PW CV 2
Range
SYNC
PW CV 2
0
0
10
010
0
10
010
-2
+2
STANDARD VCO
A-120 VCF 1
CV 2
CV 3
Audio In
CV 2
CV 3
Lev.
Res.
Freq.
CV 1
LOW PASS FILTER
0
10
0
10
010
010
010
Audio Out
CV 2
Audio In 1
Audio In 2
Audio Out
Gain
CV 1
A-130
VCA-LIN.
0
10
0
10
0
10
0
10
0
10
CV 1
In 1
In 2
Out
A-118
NOISE /
RANDOM
Colored
Random
Output
Red
Rate
Level
Random
Control
Blue
White
-+
010
010
0
10
0
10
A-110
VCO
CV 1
CV 2
PW CV 1
Tune
CV 2
PW
PW CV 2
Range
SYNC
PW CV 2
0
0
10
010
0
10
010
-2
+2
STANDARD VCO
A-145
LFO
Frequ.
Frequ.
Range
0
10
Reset In
M
H
L
A-140 ADSR
Retrig.
Output
Inver se
Output
ADSR
Control
Gate
Output
0
10
H
L
M
Time
Range
A
D
S
R
0
10
0
10
0
10
A-138
MIXER
Input 2
Input 3
Output
Input 1
Input 4
0
10
0
10
0
10
0
10
0
10
lin
exp
In 1
In 2
In 3
In 4
Out

doepfer System A - 100 3. A-100 signal flow
7
3. Signal flow in the A-100
3.1 The Principles of Voltage Control
What makes analogue synthesizers (and modular sy-
stems in particular) special is that the important para-
meters of the sound sources (VCO, noise, etc.) and
modifiers (VCF, VCA, etc.) can be altered not just by
hand, but by voltage control.
This principle was turned into reality by the “father of
the analogue synthesizer”, Robert Moog, who produ-
ced the first commercially available synthesizer in the
sixties. It gives vast flexibility and the potential to
make sounds that have never been made before.
Fig. 5 shows the principle of voltage control, with
examples of control voltages affecting a filter (VCF)
and an oscillator (VCO).
In the case of the VCF, the parameter which is being
voltage-controlled is the Cut-Off Frequency fc. The
amount of control voltage input present changes the
cut-off frequency, and thus the frequency of the signal
that the VCF lets through - see the shaded area in the
diagram.
Fig. 5: The principles of voltage control
In the case of the VCO, it’s the pitch which is control-
led by a voltage: an increase of 1 volt corresponds to
an increase of one octave in the pitch.
With a sudden change of voltage, the pitch changes
suddenly, while with a smoother, continuous change,
portamento is created.
f
c
Low Pass Filt er
Input Output
CV Input
CV
Pit c h
VCO
Output
CV Input
Out
Fr eq . Fr eq .
f
c
f
c
CV
tt

3. A-100 signal flow System A - 100 doepfer
8
As well as modules which can be affected by voltage
control, there are other modules like the ADSR and
LFO which themselves produce voltages to control
other modules.
Usually, these modules need a Trigger Signal to bring
them into action. For instance, a GATE Signal, corre-
sponding to a key being pressed on a keyboard, can
set off an ADSR, which then puts out its variable
voltage “envelope” to affect other modules (see Fig.
6).
Fig. 6: The envelope generated by an ADSR
3.2 Signals in the A-100
In the System A-100 there are three types of signal:
• Audio Signals
• Control voltages
• Trigger voltages
Audio Signals are produced by the sound source
Modules (such as VCO or NOISE), and lie in the range
from -5 V to +5 V (10 VSS). The System A-100 can also
let you use external Audio Signals (e.g. Microphone,
Electric Guitar, Keyboard).
H To interface satisfactorily, the level of exter-
nal Audio Signals must be brought up to the
A-100’s operating level.
Module A-119 (External Input), is ideal for
this job, having among other things an inter-
nal pre-amp, and two inputs of different sen-
sitivity.
Control voltages, as produced by modulation sources
like the LFO and ADSR, are typically from -2.5 V to
+2.5 V (5 VSS) for the LFO, and from 0 V to +8 V for
the ADSR.
+ 5 V
0 V
On Off
t
GATE CV Out
ADSR
t
CV Out
GATE

doepfer System A - 100 3. A-100 signal flow
9
Trigger or Gate Signals, which start a process or
function, are typically from 0 V to +5V or 0V to +12 V,
with the trigger occurring as the leading edge of the
waveform shoots up from 0 V to +5V/12 V. The A-100
modules usually output +12V, but the corresponding
inputs of A-100 modules (e.g. Gate, Clock, Reset) will
also work with lower levels (typ. +5V).
These definitions of the various signals, and the di-
stinctions between them - sound sources and modula-
tion sources - are right in principle, but a modular
system like the A-100 often makes a mockery of them.
In a modular set-up, all of the modules produce volta-
ges, and can be used as control voltages or triggers,
thus blurring the distinction between the various types.
For example, the output from an LFO can be used as
an audio signal, as a control voltage for a VCF or VCA,
or as a trigger signals for a sequence.
It’s just about true to say that anything can be modula-
ted by anything else, so that a modular system gives
the musician extraordinary flexibility and individuality.
3.3 The System Bus in the A-100
The A-100’s System Bus supplies power to the modu-
les. It also carries the internal control system
(INT.GATE and INT.CV), which some of the modules
(such as the VCO A-110, or ADSR A-140) can tap into.
You can choose whether these modules receive these
signals, by altering an internal jumper.
Fig. 7: The A-100 system bus
If you use the A-190 MIDI-/CV-Interface in your sy-
stem, when you press a key on your MIDI keyboard,
the gate and CV1 signals from the A-190 will be sent
via the INT.GATE and INT.CV to all modules on the
bus.
The INT.GATE and INT.CV signal busses can be split
into two equal halves by removing jumpers J1 and
J2 (see Fig. 7), so that for each whole bus, you can
have two separate CV/GATE subsystems.
INT. Gate
INT. CV
+5 V
+12 V
GND
-12 V
1
7
8
14
J1
J2

3. A-100 signal flow System A - 100 doepfer
10
If on the other hand you’d like to have the same
internal CV and gate available on two busses at
once, you need to link the two together, with the
special CV/gate leads, the A-100 BC.
This is how you go about it:
D Remove the A-100 from the electrical supply.
D Remove Jumpers J1 and J2(see p.9) from the
upper (see Fig. 8 !) and lower (see Fig. 8 ")
system bus boards.
D Replace the jumpers with the special CV / gate
leads, A-100 BC (see Fig. 8 1, 2).
AMake absolutely sure that you connect the
leads correctly, joining up the upper INT CV
with the lower INT CV, and the upper INT
GATE with the lower, to avoid possible
damage when you switch back on! Fig. 8: Making a common INT.CV and INT.GATE
signal path between the upper and lower
busses.
➀➁



doepfer System A - 100 3. A-100 signal flow
11
3.4 Integrating the A-100 with MIDI
To link the A-100 into a MIDI system, you can use
external MIDI interfaces like our MCV4, MSY2 or
MCV24.
The MIDI-CV/SYNC Interface A-190-1 is a MIDI-to-
CV/Gate/Sync interface with the following outputs:
• CV 1 (for pitch control, 12 Bit)
• CV 2 (any MIDI-Controller, 8 Bit)
• Gate
• Clock
• Start / Stop
The A-190 automatically sends pitch control CV and
gate information out on the INT.CV and INT.GATE
busses.
Another solution is the usage of the low cost MIDI-CV
Interface A-190-2 which has one Gate and four CV
outputs available.
Another suitable MIDI-CV Interface for A-100 was the
24-channel MCV24, a 19” rackmount with its own
power supply. As the MCV24 is no longer in production
you will have to try to find a second hand unit.
VC Modules like the A-141 VC-ADSR and A-147
VC-LFO can be controlled via the A-190-1 or A-190-2,
so that, for instance, a continuous MIDI controller can
alter envelope parameters in real time. Since these
controllers can be recorded by a MIDI sequencer, VC
modules are effectively programmable.
Analog sequencing can be provided by the A-155 or
the external MAQ 16/3 MIDI Analog Sequencer.
To convert up to 16 control voltages in the range
0...+5V (e.g. from a Theremin A-178 or Joy-Stick
A-174-1 or Foot-Controller A-177-2 or ribbon controller
A-198) into MIDI controllers the CV-to-MIDI interface
A-192 is the right choice.
doepfer System A - 100 3. A-100 signal flow

3. A-100 signal flow System A - 100 doepfer
12
3. A-100 signal flow System A - 100 doepfer

doepfer System A - 100 4. A-100 Basic System
13
4. A-100 Basic Systems
It’s not in the nature of modular systems to have hard
and fast rules about which modules should be inclu-
ded. But if you’re just starting out along the modular
path, it may be difficult to choose a sensible first set of
modules. Accordingly, we’ve designed Basic Systems
with all the modules mounted in a rack system, and 30
patch leads thrown in as well. For an exact run-down
of the modules included in Basic System 1 (A-
100BS1), see the table on the right of this page, and
the illustration on the next page. To integrate BS1 it
into a MIDI system, you would need a separate MIDI
interface, such as an MCV4 or MCV24. In the Basic
System 2 (A-100BS2) the MIDI interface A-190 is
included (instead of A-150 and A-162). We also have
available a small Mini System (A-100MS). See our
topic prospectus for details.
The purpose and function of other modules will be-
come more apparent as you work with your system,
and you will be able to decide which extra modules you
need for your particular purposes.
In the future other types of complete systems may be
available. We are planning an Expansion System con-
taining nearly all modules not included in the Basic
Systems, a Vocoder System and a Sound Processing
System without VCO’s for external audio signals.
Pos. Quantity Module Function HP
2 A-110 VCO 20
1 A-114 Dual Ring Modulator 4
u 1 A-115 Audio Divider 8
p 1 A-116 Waveform Processor 8
p 1 A-138b Mixer (log) 8
e 1 A-120 VCF 1 - 24 dB Low Pass 8
r 1 A-121 12 dB Multimode Filter 12
1 A-130 VCA (lin) 8
1 A-131 VCA (log) 8
1 A-118 Noise / Random 8
1 A-148 Dual Sample & Hold 4
l 2 A-145 LFO 16
o 1 A-160 Clock Divider 4
w 1 A-161 Clock Sequencer 4
e 1 A-180 Multiples 4
r 1 A-138 a Mixer (lin) 8
1 A-170 Dual Slew Limiter 8
1 A-150 Dual VCS 4
1 A-162 Dual Trigger Delay 8
2 A-140 ADSR 16

4. A-100 BS Basic system System A - 100 doepfer
14