Back catalogue: Studio Equipment

Notes: The A-100LC1v is a smaller version of the A-100LC3 with 48 HP of space. It is made out of raw wood, a black coating gives the Eurorack frame a vintage look. The built-in power supply, type A-100SSB, delivers up to 380 mA at +12 V and -12 V as well as 100 mA at +5 V.

The A-100LC1v comes equipped with one 48 HP measuring row for 3U modules. Its power supply features eight connectors for oscillators, filters and so forth. The case is connected to the grid via an IEC power socket.

Notes: Bus board to connect 14 modules

An assembled and tested bus board, 22 sockets, e.g. for customers who want to built their own case and need a bus board for A-100 modules, includes cables for connection to +/-12V power supply (4 wires with flat connectors on both ends, length about 30cm), but no mechanical parts (e.g. screws, spacers, nuts, washers).

In the new version of the A-100 bus board (labeled Version 6 / 2019) boxed pin headers are used which are equipped with a reverse protection (gap for the "nose" of the socket of the bus cable). When the bus cable coming from the module is connected to the boxed header in question the "nose" has to point to the right. The polarity of the cable is correct if the red wire of the bus cable then points to the bottom (to the continuous line labeled"RED WIRE" on the pc board). If this is not the case please do not connect the module to the bus board ! Otherwise both the module and the power supply (A-100PSU3) may be damaged ! In that case please contact the manufacturer of the module and ask for a suitable bus cable with the correct polarity of the connector.

The bus cables of original A-100 modules manufactured by Doepfer are equipped with suitable bus cables since 2012. Only for older A-100 modules manufactured before 2012 it may happen that the polarity of the 16 pin female connector of the bus cable is wrong (nose points to the left when red wire points to the bottom). This is because in the past unboxed pin headers were used and the position of the "nose" did not matter. In such a case please contact Doepfer or one of their dealers and order a suitable bus cable.

Notes: Blank panel, 8HP, constructed from anodised aluminium, black.

Notes: Blank panel, 8HP, constructed from anodised aluminium, silver.

Notes: Blank panel, 4HP, constructed from anodised aluminium, black.

Notes: Blank panel, 42HP, constructed from anodised aluminium, silver.

Notes: Blank panel, 4HP, constructed from anodised aluminium, silver.

Notes: Blank panel, 2HP, constructed from anodised aluminium, silver.

Notes: Blank panel, 1.5 HP, constructed from anodised aluminium, silver.

Notes: Blank panel, 1HP, constructed from anodised aluminium, silver.

Notes: High quality rotary knob, for use with Doepfer or a wide range of modules. Robust design with indented edges. Retro style finish.

Notes: High quality rotary knob, for use with Doepfer or a wide range of modules. Robust design with indented edges. Yellow finish.

Notes: High quality rotary knob, for use with Doepfer or a wide range of modules. Robust design with indented edges. Red finish.

Notes: High quality rotary knob, for use with Doepfer or a wide range of modules. Robust design with indented edges. Grey finish.

Notes: High quality rotary knob, for use with Doepfer or a wide range of modules. Robust design with indented edges. Green finish.

Notes: A-100SSB is a combination of power supply and bus board with 8 connectors for A-100 modules, planned for applications with up to 8 modules and a max. current of 380 mA.

- Wide range mains voltage input 100-240V AC / 50-60 Hz
- IEC inlet on board for the connection of a suitable mains cable (a suitable mains cable has to be purchased by the customer locally, it's not included with the A-100SSB)
- Switching supply with +12V/380 mA and -12V/380mA for the operation of A-100 modules up to 380 mA total supply current
- Safety cover at the bottom side (covers all elements that lead mains voltage)
- On board fuse
- 8 bus connectors
- LED displays for +12V, -12V and +5V
- Dimensions: about 270 mm (length) x 55 mm (width) x 35 mm (height)
- Several 3mm holes for mounting the unit on a rear panel or bottom plate

Notes: - 6.3 mm jack male mono to 3.5 mm jack male mono
- Length: 3 metres

Notes: - 6.3 mm jack male mono to 3.5 mm jack male mono
- Length: 1.5 metres

Notes: Patch cable for modular synthesizer 80 cm, transparent, mono jack plug 3.5 mm at each end.

Notes: - High-grade patch cable designed for modular units
- 3.5mm mono jack plugs
- Length: 80cm
- Red finish

Notes: - High-grade patch cable designed for modular units
- 3.5mm mono jack plugs
- Length: 50cm
- Transparent cabling

Notes: - High-grade patch cable designed for modular units
- 3.5mm mono jack plugs
- Length: 50cm
- Angled connector on one end
- Orange finish

Notes: - High-grade patch cable designed for modular units
- 3.5mm mono jack plugs
- Length: 50cm
- Grey finish

Notes: - High-grade patch cable designed for modular units
- 3.5mm mono jack plugs
- Length: 30cm
- Black finish

Notes: - High-grade patch cable designed for modular units
- 3.5mm mono jack plugs
- Length: 200cm
- Green finish

Notes: - High-grade patch cable designed for modular units
- 3.5mm mono jack plugs
- Length: 15cm
- Yellow finish

Notes: - High-grade patch cable designed for modular units
- 3.5mm mono jack plugs
- Length: 120cm
- Blue finish

Notes: Module A-199 is a spring reverb module. The reverb effect is electronically simulated by means of 3 spiral springs. Spring reverb systems have a very characteristic sound that is based on the (insufficient) mechanical properties of the springs like signal delays, audio resonances, limited frequency range, acoustic feedback behaviour, sensitivity to mechanical shocks and others.

The 3-spring system used in the A-199 ensures a "dense" reverb because of the different properties of the three springs.

The A-199 implies some special features that are not self-evident for spring reverb units:

The reverb signal can be fed back to the input using the Feedback control. Even self-oscillation of the springs similar to the self-oscillation of filters is available. The feedback loop can lead even via external modules like VCA, VCF, phaser, frequency shifter, vocoder, distortion/waveshaper, ring modulator and others. In this case the reverb output of the A-199 is connected to the input of the external module(s) and the output of the external module(s) is fed back to the Ext. Feedback In socket of the A-199. This socket contains a switch that interrupts the internal feedback loop as soon as a plug is inserted.

Another feature is the Emphasis control. This enables the adjustment of the accentuation of middle frequencies (around ~ 2kHz).

With the Mix control the relation between original and reverb signal appearing at the mix output is adjusted.

Using all these features very extreme and unusual effects can be generated with the A-199.

Notes: Module A-197-3 is a control unit for RGB LED stripes. The LED stripe is glued e.g. to the inner edges of the cases A-100P6/P9/PMS6/PMS9/PMS12 to illuminate the modules and patching statically or dynamically. Especially during live events the dynamic illumination in sync with the sound is an eye-catcher. Each colour (red, green, blue) has available a manual control for the background brightness and a CV input with attenuator that enables the dynamic brightness controlled by other control voltages of the modular system. For example three envelopes can be used which also control the loudness or filtering of sound processing modules. But even other control applications are possible, e.g. LFO, random voltages, clock/gate/trigger signals, sequencer, Midi-to-CV.

Notes: Module A-192-2 contains two independent CV/Gate-to-Midi/USB interfaces. For each of the two sub-units these inputs are available:

- Gate Input (min. +5V)
- CVN Input (defines the Midi note number), 1V/octave standard, range 0...+10V (i.e. 10 octaves)
- CVV Input (defines the velocity value assigned to the Midi note message), can be used alternatively for Midi volume (CC#7), range 0...+5V
- CVC Input (free assignable to any Midi control change number), range 0...+5V

For both sub-units a common CV Transpose input is available (1V/octave, range 0...+10V). The voltage applied to this input is added internally to CVN before the Midi note number is generated. It can be used e.g. to transpose two sequences simultaneously by one voltage.

How it works:

Whenever the rising edge of the Gate input is recognized a Midi note on message is generated. The note number corresponds to the sum of the voltages applied to the CVN input and the common CV Transpose Input that is present at the rising edge of the gate signal.

Notes: USB/MIDI to clock interface that allows for synchronizing clock-driven modules with the MIDI environment. It processes only the Clock, Start, Stop and Continue MIDI commands. It has several clock divider outputs, each one start, stop and reset outputs for controlling sequencers and also an interesting wait function. Input is either a 5-pin DIN socket or USB.

Notes: Module A-184-2 is the combination of two functions and planned primarily as an expansion module for VCOs or LFOs (e.g. A-110-1, A-110-2, A-145, A-147-2).

Triangle-to-Sine Waveshaper:

The upper section is a very precise triangle-to-sine converter (thanks to Tim Stinchcombe who recommended this circuit). It can be used to convert any triangle waveform into a (nearly) perfect sine. The converter is much better than the simple diode converter used in the A-110-1, A-111-1, A-145 and A-147-2. Two trimming potentiometers are used to optimize the sine shape. The converter should be assigned to one VCO or LFO because the trimming potentiometers have to be re-adjusted if the input level or DC offset of the input signal changes. If the trimming potentiometers are deliberately mis-adjusted it can be used also as a waveshaper for non-sine waveforms (e.g. sine-shaped at the top of the signal and a peak at the bottom, even voltage controlled by applying an additional voltage to the waveshaping circuit, "circuit-bending" notes will be available).

The waveform converter is DC coupled and can be used also for low frequencies (e.g. LFO triangle waves).

Voltage Controlled Crossfader:

The lower section is a voltage controlled crossfader. It has two inputs A and B. The two signals are mixed together with variable percentage. When the manual control CF is fully CCW only signal A appears at the CF Out socket. When the manual control CF is fully CW only signal B appears at the CF Out socket. In the centre position of the manual control both signal appear with the same level. In addition a control voltage input CV with attenuator is available to enable voltage control of the crossfade.

Two LEDs display the crossfading shares of input A and B.

The crossfader uses two high quality VCAs (SSM2164). Inputs and outputs are DC coupled. Consequently it can be used for audio signals and slowly varying control voltages as well.

The sockets of the upper section (triangle and sine) are normalled to the inputs A and B of the crossfader section. That way the crossfader is used to fade between triangle and sine of the VCO or LFO connected to the waveshaper. If other signals are plugged into the input sockets A and B these signals are used for crossfading.

The main application is to fade between two different waveforms of a VCO or LFO or two different VCF outputs. But the module can be used for any other signals too as the waveshaper and crossfader sections are independent apart from the normalled sockets.

Notes: Module A-183-9 is a simple power supply for up to four devices which can be powered via USB (e.g. keyboards, smartphones). An LED shows is the +5V are present.

The module has no USB function but provides only the +5V supply for USB devices.

A control LED shows if the +5V are present.

Note: The module requires an A-100 case with built in power supply A-100PSU3. Only this A-100 supply has the required +5V available. We do not recommend the usage of an older A-100 case with A-100PSU2 as this would require the +5V adapter A-100AD5 and the max. current would be limited to 100mA.

Notes: Module A-182-1 is a simple passive multi-connector similar to the multiples modules A-180-1/A-180-2. In contrast to modules A-180-1/2 each socket is equipped with a 3-position switch that allows to connect the corresponding socket to the internal bus #1 (left position), bus #2 (right position) or to turn the socket off (centre position).

Examples:

- All switches in left position or all switches in right position: 8-fold multiple

- Four switches in left position and four switches in right position: two 4-fold multiple

- X switches in left position, Y switches in right position and Z switches in centre position: two separate multiples with some sockets turned off

Notes: Module A-180-3 is a dual buffered 1-in-3 multiple. The signal applied to the input socket appears as a buffered signal at the three output sockets. Each output has its own buffer, i.e. the three output sockets are not simply connected to each other. The lower output of the upper unit is normalled in the factory to the input of the lower unit. That way the module works as a single 1-in-6 buffered multiple provided that no signal is applied to the input of the lower unit. But it's also possible to pick-up the bus CV and normalize the input socket of the lower unit to the bus CV.

Application: copying/buffering of CV, gate and audio signals.

Notes: 2HP narrow version of the A-180 multiples module. It is a passive signal splitter suitable for audio or CVs. Two sets of four jacks are interconnected, by placing a solder bridge you can connect all eight jacks.

Notes: Module A-179-2 can be used to convert different illumination intensities into corresponding analog voltages and a gate signal derived from the analog voltage. It's the successor of the obsolete module A-179.
A light sensitive resistor (LDR) converts the illumination of the internal light sensor into a corresponding analog control voltage. The internal sensor is located at the front panel. Instead of the internal sensor a remote sensor can be connected via a standard patch cable to the module (ext.Sens. socket). An external sensor with a 2 m patch cable (A-100C200) is included. The external sensor is mounted on a small pc board which is equipped also with a 3.5 mm jack socket. The nut of the socket can also be used to mount the external sensor.

The module A-179 is similar to the Theremin module A-178 but uses the illumination intensity instead of the distance between hand and antenna for generating the analog voltage.
One can choose between passive control by covering/shading the sensor via hand or body, or active control by using e.g. a pocket lamp or flashlight. For this two versions of output voltages are available (CV Out + und CV Out -).

The module has these controls and in/outputs available:

ext. Sens.: by means of a standard patch cable the external sensor can be connected to this socket. In this case the internal sensor is turned off.

CV Offset: control to adjust the output voltage which is assigned to a certain illumination (e.g. 0V for complete darkness)

CV Level: control that is used to adjust the sensitivity of the generated output voltage (i.e. how much a certain difference in brightness affects the output voltage)

Gate Threshold: control that is used to adjust the threshold for the generation of the gate signal, an internal jumper is used to define if the gate signal is derived from the CV Out+ or CV Out- voltage.

CV Out+: positive control voltage output, increasing brighness causes the increase of the voltage at this output

CV Out+: negative control voltage output, increasing brighness causes the decrease of the voltage at this output

LED CV Out: bipolar LED (red/yellow) as display for the CV outputs

Gate: gate output with LED display

Applications:

controlling any voltage controlled parameter e.g. pitch or pulswidth of a VCO, filter frequency or resonance of a VCF, loudness of a VCA, time of an envelope generator, frequency of a VCLFO
triggering activities via gate with adjustable threshold, e.g. starting an envelope, starting/stopping a sequencer or any switching function (e.g. with A-150-1 or 151).
Conversion into MIDI control change messages is possible with the A-192-2.

Width: 4 HP / 20.0 mm
Depth: 30mm (measured from the rear side of the front panel)

Notes: Theremin module for generating a variable control voltage by approaching/removing hand to/from an antenna.

The distance range is about 30 cm. Additionally the module is equipped with a Gate output with adjustable threshold level. To simulate the original Theremin two A-178, a VCO (e.g. A-110) and a linear VCA (e.g. A-130 or A-132) are required. But of course the A-178 can be used to control other functions in the A-100 (e.g. filter frequency, modulation depth and/or speed, tempo, attack/decay time and so on).

The CV output voltage of the A-178 can range - according to the setting of the front panel controls - from -10V...+10V.

The gate output switches from 0V to about +10V.

Power consumption: 60mA at +12V and 20mA at -12V

Depth: 40mm

HP : 8

Notes: Module A-174-4 modules outputs three control voltages generated by a spring-loaded X/Y cross potentiometer (so-called joy stick) and a Gate signal. The control voltages for X and Y are controlled by the X and Y position of the joystick in the usual way. The third control voltage Z is controlled by the rotation of the spring-loaded joystick knob. The Gate signal is generated by a button at the center/top of the joystick knob.

For each control voltage the non-inverted signal (X, Y, Z) as well as the inverted signal with adjustable offset (-X+XO, -Y+YO, -Z+ZO) are available. The generic joystick control voltages are bipolar, i.e. they range from typ. -5V (lowest position) via 0V (center position) to typ. +5V (highest position). The "Overlap" switches can be used to add a fixed offset voltage of typ. +5V to the non-inverting output in question so that the output voltage range changes to typ. 0...+10V (rather than -5...+5V). That's necessary if e.g. a VCA has to be controlled, which requires a pure positive control voltage range. The switches are named "overlap" because they allow the overlapping of the non-inverting CV output (X, Y, Z) with the inverting output (-X+XO, -Y+YO, -Z+ZO) for crossfading applications. With the overlap switch "on" and appropriate setting of the offset control it's possible to obtain a control voltage range of 0...+10V for the non-inverting output and +10V...0V (i.e. same range but opposite direction) for the inverting output.

The offset voltages which are added to the inverting outputs can be adjusted by means of three small potentiometers. That way different kinds of control voltage ranges are possible, e.g.
-5V ... +5V for the non-inverting output and +5V ... -5V for the inverting output ( Overlap = off, Offset = 0)
0 ... +10V for the non-inverting output and +10V ... 0V for the inverting output ( Overlap = on, Offset = max)
-5V ... +5V for the non-inverting output and +10V ... 0V for the inverting output ( Overlap = off, Offset = max)
0 ... +10V for the non-inverting output and +5V ... -5V for the inverting output ( Overlap = on, Offset = 0)
On top of this the four quadrant voltages Q1, Q2, Q3 and Q4 are available. A quadrant voltage becomes positive when the joystick is positioned in the quadrant in question.
Each CV output is equipped with an LED that displays the present voltage.

Because of the construction height of the joystick (about 7 cm) the module cannot be installed into the cases A-100P6, A-100P9, A-100PMS6, A-100PMS9 and A-100PMS12 during transportation as the depth of the case cover is not sufficient. Into the base cases A-100PB and A-100PMB as well as in all other cases without cover the module can be installed without problems.

HP : 12

Notes: Module A-171-2 is a voltage controlled slew limiter with a lot of additional features beyond a simple slew limiter. It's mostly a licensed copy of Ken Stones VCS which is in turn based on the Serge VCS.

Typical applications:

- VC Slew Limiter / VC Portamento / VC Low Pass Gate:

Cycle switch = off, no trigger signal applied to Trig socket: Voltage controlled Slew limiter or portamento generator: the signal applied to the signal input is "slewed". The slew up and down times are controlled manually by means of the Up and Down controls, the effect of the CV Up and CV Down control voltages are controlled by the CV Up and CV Down controls, in exponential mode these controls also affect the slew shape (see symbols at the CCW and CW positions of the controls).

If an audio signal is applied an short slew rates are chosen the module works as a simple VCF/VCA combo.

- A/D Envelope Generator / Pulse Delay / Subharmonic Generator:

Cycle switch = off, trigger signal applied to Trig socket, no input signal: Simple Attack/Decay envelope Generator, the rise and fall times are controlled like the slew up/down times above, including the shape of the falling/rising slope of the envelope, the exp. CV input can be used to change both attack and decay simultaneously.

At the End output a pulse appears as the end of the envelope is reached (less than about 20mV), this can be used as a pulse delay.

If a series of triggers are applied to the VCS faster than the total rise and fall times, the module will divide the incoming signal by a whole number. In the audio range the output will be the sub-harmonic series.

- VCLFO / VCO:

Cycle switch = on, no trigger signal applied to Trig socket, no input signal: Voltage controlled LFO/VCO, the rise and fall times of the waveform are controlled like the slew up/down times above, including the shape of the falling/rising slope
the exp. CV input can be used like the CV input of a VCO or VCLFO, the response is exponential but not exactly 1V/oct.

Notes: Module A-160-5 is a voltage controlled clock multiplier. The incoming clock signal (socket Clock In) is multiplied by a factor that depends upon the control voltage on socket CV In (0...+5V) and the position of the Mode switch. The multiplied clock signal is available at the socket Clock Out. According to the position of the Mode switch different clock multiplying factors are assigned to the control voltage. With 0V CV no clock output is generated. This state is indicated by "all LEDs off". With increasing CV integer factors (left position of the mode switch), power of two factors (middle position) or a mix of both (right position) are obtained. Nine LEDs are used to show the currently selected multiplying factor. In addition two LEDs are used to display the incoming and outgoing clock signal.

A manual control is used to adjust the clock multiplication factor manually without the need of an external control voltage. The voltage generated by this control ("Manual") is normalled to the CV In socket. As long as no plug is inserted into the CV In socket the clock multiplication factor is adjusted by means of the manual control knob and displayed by the LEDs. For dynamic applications (like the ratcheting function described below) the manually generated CV is overwritten by the external CV which has to be fed into the CV In socket.

The module can be used for all kind of clock multiplying applications. One important example is the generation of so-called ratcheting sequences. The band Tangerine Dream is famous for this kind of sequences. A normal sequencer generates only one gate signal per step. A ratcheting sequence may have also more than one gate pulses per step. This function can be obtained by using the A-160-5: one CV output of the sequencer is used to define the number of gate pulses per step. If the control of the step in question is fully CCW the generated CV is 0V and no gate signal is generated (mute of the step). When the control of the step in question is turned clockwise one, two or more gate pulses are generated depending upon the position of the mode switch and the voltage generated by the CV at this step.

Technical note: Due to the nature of clock multiplying it takes a few input clock pulses until the clock output is stable. One has to average a few input clock pulses to generate the multiplied clock output signal. Even when the input clock frequency changes it will take a few cycles until the output clock signal is correct as the module cannot foresee the future of the clock input signal. The generated clock output signal is derived from the last few cycles of the clock input signal. Consequently the module should be driven only by a clock signal with constant or slowly changing frequency.

Notes: Module A-160-2V is an enhanced version of the standard clock divider A-160. The module is a frequency divider for clock/trigger/gate signals, designed to be a source of lower frequencies, particularly for rhythm uses.

The Clock input will take any digital signal from, eg., an LFO, MIDI sync, or the gate from a MIDI-CV interface. At the outputs, you have access to three sets of seven different sub-divided clock signals, from half the clock frequency down to 1/128. The low/high levels of the output signals are 0V and about +10V.

The A-160-2V also has a reset input. Whenever a reset signal is sensed, all outputs are set to certain levels which depend upon the selected mode.

HP : 4

Notes: Module A-160-2 is an enhanced version of the standard clock divider A-160. The module is a frequency divider for clock/trigger/gate signals, designed to be a source of lower frequencies, particularly for rhythm uses. The Clock input will take any digital signal from, eg. LFO, MIDI sync, or the gate from a MIDI-CV interface. At the outputs, you have access to three sets of seven different sub-divided clock signals, from half the clock frequency down to 1/128. The low/high levels of the output signals are 0V and about +10V.

The A-160-2 also has a reset input. Whenever a reset signal is sensed, all outputs are set to certain levels which depend upon the selected mode.

These are the most important features of the module:

Three different sets of dividing factors, selected by a three-position switch at the front panel:
- Power of two: 2, 4, 8, 16, 32, 64, 128
- Prime numbers: 2, 3, 5, 7, 11, 13, 17
- Integer: 2, 3, 4, 5, 6, 7, 8

Two output modes, selected by a two-position switch at the front panel:
- Gate mode: outputs act like the outputs of typical binary dividers
- Trigger mode: in this mode the outputs are AND-wired with the clock signal (i.e. the clock pulsewidth affects the pulsewidth of the outputs)
- Clock edge type selected by a jumper on the pc board:
- Positive: the rising edge of the clock signal triggers the state change of the outputs
- Negative: the falling edge of the clock signal triggers the state change of the outputs

Reset behaviour by two jumpers on the pc board:
- Level triggered: the level at the Reset input triggers the Reset
- Edge triggered: the edge of the signal at the Reset input triggers the Reset
- Positive: a high level (> 2.5V) or the rising edge at the Reset input triggers the Reset
- Negative: a low level (< 1 V) or the falling edge at the Reset input triggers the Reset

Output polarity selected by a jumper on the pc board:
- Positive: non-inverted outputs
- Negative: all seven outputs are inverted

Width: 4HP / 20mm
Depth: 35mm (Measured from the rear side of the front panel)
Current: +12V: +50mA, -12V: -0mA

Notes: Module A-160 is a frequency divider for clock/trigger/gate signals, designed to be a source of lower frequencies, particularly for rhythm uses. The Trigger input will take clock signals from, e.g. an LFO, MIDI sync, or the gate from a MIDI-CV interface.

At the outputs, you have access to the sub-divided clock signals, from half the clock frequency down to 1/64. The low/high levels of the output signals are 0V and about +10V.

The A-160 also has a reset input. Whenever a reset signal is sensed, all outputs are set to zero, until the reset voltage disappears.

The Clock Divider can be used in combination with the A-161 Clock Sequencer to produce stepped sequences with a length of from one to eight events.

Notes: Module A152 is a very useful switching and T&H module. It combines a voltage addressed 1-to-8 multiplexer and 8 fold T&H that can be used as kind of an analogue shift register too. The active in/output is displayed by a LED. The digital output of the currently addressed step outputs "high". The remaining digital outputs are low.

Instead of voltage control even clock/reset controlled addressing of the active step is possible. The rising edge of each clock signal causes an advance to the next state. The rising edge of the reset signal resets to step 1.

The sum of the voltages coming from the manual Address control and the CV input define the currently addressed step of the 3 sub-devices. If the module is controlled by clock and reset the control voltage has to remain unchanged as the CV control has priority over the clock/reset control (e.g. simply turn the CV control fully counter-clockwise and do not touch the Address control knob).

Sub-device #1 is the bidirectional 8-fold multiplexer (kind of an electronical 8-fold rotary switch). Bidirectional means that it works into both directions like a mechanical rotary switch: the common socket may work as an output that is connected to one of the 8 inputs that are e.g. connected to modulation or audio sources. But the common socket may even function as input. In this case the signal applied to the common socket is output to the currently addressed single socket. The voltage range of the in/outputs to be switched is the full A-100 voltage range -12V....+12V. All A-100 signals can be switched without any restrictions.

Sub-device #2 is the addressed 8-fold T&H. The signal at the common T&H input is connected to the addressed T&H output. As soon as a new output is addressed the last voltage is stored at the output (Track&Hold function). The T&H section of the A-152 allows the emulation of the "toggling T&H" function of the Buchla module 266 "Source of Uncertainty". Only the first two T&H outputs of the A-152 are required for this application. This unit can be used also as kind of an analogue (shift) register. The difference to a "real" analogue shift register is that the sampled output voltages are not shifted to the next output but remain allocated to the same output. But in some cases (e.g. controlling the pitch of 3 VCOs by 3 output voltages of the A-152) the result is the same.

Sub-device #3 is the digital output section. The digital output of the currently addressed turns to "high". All other digital outputs are low. The digital outputs can be used to trigger e.g. envelope generators or to control the reset input in the clocked mode to reduce the number of addressed stages.

Notes: Module A-151 (Quad Sequential Switch) is like an electronic four-position rotary switch.

It includes trigger and reset inputs, four in/outputs, and a common out/input. Each time a pulse is received at the trigger input socket, the common out/input is connected to the next in/output. After the fourth in/output, the next trigger makes it step back to the first again, and so on. A positive pulse at the reset input switches the out/input immediately back to the first in/output. Voltages in the range -8V...+8V at the O/I resp. I/O sockets can be processed by the module.

Four LED's indicate the active in/output (ie. the one that is connected to the out/input at any particular time).

Notes: Module A-151 (Quad Sequential Switch) is like an electronic four-position rotary switch.

It includes trigger and reset inputs, four in / outputs, and a common out / input. Each time a pulse is received at the trigger input socket, the common out / input is connected to the next in / output. After the fourth in / output, the next trigger makes it step back to the first again, and so on. A positive pulse at the reset input switches the out / input immediately back to the first in / output (see Fig. 1). Voltages in the range -8V...+8V at the O/I resp. I/O sockets can be processed by the module.

Four LEDs indicate the active in / output (i.e. the on that is connected to the out / input at any particular time).

Notes: Module A-150-1 (Dual VCS) contains two separate voltage-controlled switches.

Each switch has a control voltage input, a common Out / Input, and two In / Outputs. The switches are bi-directional: they can work in both directions, so can connect one input to either of two outputs, or either of two inputs to one output. Voltages in the range -8V...+8V at the O/I resp. I/O sockets can be processed by the module.

Two LEDs show which in / output is active (i.e. which is connected to the common out / input).

Notes: Module A-149-4 generates four triggered random voltages which meet the criteria choosen by several controls.

Manual controls for the criteria selection:

Octave range (manual control "Oct."): this parameter defines how many octaves are covered by the random voltages (0 ... +5V, with "Oct." control fully CCW only 0V are generated)

Grid (6 illuminated radio buttons): this parameter defines the grid of the random voltages:

Octaves (Oct)

Octaves + Quin (Quint)

Chords

Scale

Semitones

continuous (i.e. stepless)

Minor / Major (2 illuminated radio buttons): this parameter defines in case of chords or scales if they are minor or major. For all other grids this parameter has no meaning

Sixth / Seventh (2 illuminated separate buttons): these parameters defines if the sixth or seventh is added. Valid only if Oct, Quint, Chord or Scale is chosen as grid.

The output voltages follow the 1V/octave standard with exception of the Continuous mode. The voltages in this mode are totally random and do not follow the 1V/oct standard (i.e. not a multiple of 1/12V).
The generation of a new random voltage at the output (CV Out 1...4) is triggered by the corresponding trigger input (Trig. In 1...4). The trigger inputs are normalled top down. The minimum trigger level is +2.5V (up to max. +12V).

Applications:

random polyphonic structures (in combination with the polyphonic modules A-111-4, A-105-4, A-132-8, A-141-4 and e.g. A-157 as trigger source and A-173-1/2 for transposition of the polyphonic structures)

any application that requires several random voltages

Width: 4 HP / 20.0 mm
Depth: 45mm (measured from the rear side of the front panel)

Notes: Module A-148 (Dual S&H) has two identical sample & hold modules, designed to produce 'staircase' voltages. The signal present at the sample input is sampled at a rate set by the signal at the trigger input, and held at that voltage at the S&H output.

The exact shape of the staircase depends on the sort of waveform at the sample input: NOISE or RANDOM signals produce random patterns; an LFO produces rising or falling staircase patterns.

Two LEDs for each S&H indicate the voltage (positive or negative) of the sampled signal.