Module A-101-8 is a 8-stage phase shifter which uses light-sensitive resistors (LDR) and is a replica of the Compact Phasing A manufactured by the company Schulte in the seventies. The actual phasing circuit is identical to the historic model. Only the illumination control of the LDRs is different: the A-101-8 uses LEDs to illuminate the LDRs, the historic model used incandescent miniature lamps. And the A-101-8 has no built-in LFO but can be controlled by any external control voltage source (e.g. LFO, ADSR, random, Theremin, ribbon controller, sequencer, midi). The phasing offset (i.e. the base value for the phase shifting) and the modulation depth of the external control signal can be adjusted separately. The Compact Phasing A had no offset control but only a depth control for the built-in LFO. Feedback and mixing ratio of the output signal are set by two controls. The audio input is equipped with an attenuator. The module has two audio outputs available (same as the historic model) and a visual display of the phase shifting.

The module has these controls and in/outputs available:

• Control Man. : manual control of the phase shift offset (base value)
• Control CV: attenuator for the signal applied to the CV socket
• Control Feedb.: Feedback or Resonance (similar function as filter resonance/feedback/emphasis)
• Control Mix: sets the mixing ratio between original and phase shift signal appearing at output 1
  • fully CCW: only the modified input signal appears at output 1 (see note below *)
  • center: a mixture between the modified input signal and the phase shift signal appears at output 1, that's the standard position for the classical phasing effect
  • fully CW: the pure phase shifted signal appears at output 1 (e.g. for vibrato effects)
• Control Input Level: attenuator for signal applied to the In socket
• Socket In: audio input
• Socket CV: control voltage input 
• Socket Out 1: audio output 1 (mix signal)
• Socket Out 2: audio output 2 (modified input signal)
• LED: visual control of the phase shift

The module has some peculiarities (same as the historic model):

• The input signal is processed at first by a pre-stage which outputs a "modified" input signal (*). This signal is not processed by the phase shift stages but is affected by the feedback setting. Only when feedback is set to zero this signal is identical to the input signal. Otherwise it contains feedback components.
• This signal is output on socket Out 2.
• When both output sockets Out 1 and Out 2 are used as stereo channels one obtains a spatial stereo sound effect. 
• The same signals is also used for the CCW position of the mix control. With mix control fully CCW the unmodified signal appears only if the feedback control is set to zero. Otherwise it contains feedback components.
• The historic model had two audio inputs: one 5-pin DIN socket and a 1/4" jack socket. The DIN socket was intended for high-level line signals. When the 1/4" jack socket was used the amplification of the pre-stage increased by about 100. The 1/4" jack socket was intended for low level signals (e.g. electric guitars or microphones). For this feature the A-101-8 has an internal jumper that can be used to increase the amplification. As long as the module is used within the A-100 system usually the lower amplification is used to avoid distortion.
• The 8 photo resistors and LEDs are assembled within an small lighproof box. In addition the pc boards are made of lighproof black material to avoid interfering light from other modules or the bus board.

Merk:

Doepfer

Type:

Chorus, Phaser, Flanger

Nummer:

A-101-8

Diepte:

45mm

Breedte:

4HP

Power:

30mA @ +12V, 30mA @ -12V

Module A-116 provides voltage-controlled dynamic waveform modification of audio signals. It can produce new waveforms from the standard VCO shapes, and modulate these changes in real time. The signal first of all goes through an input amplifier, which can attenuate the signal as well as amplify it by up to a factor of 2. After the input amplifier, the signal goes through two parallel processors: a clipping circuit, and an asymmetrical amplifier. The processed signals are added together and sent to the output. Clipping-Level and Symmetry amounts are not just manually controllable, but can also be modulated by control voltages, to produce complex, constantly changing waveforms.

Merk:

Doepfer

Type:

Distortion, Waveshaper

Nummer:

A-116

Diepte:

40mm

Breedte:

8HP

Power:

20mA @ +12V, 20mA @ -12V

A-137 is a voltage controlled Wave Multiplier. The basic idea of a wave multiplier is to multiply the waveform of an incoming signal (e.g. triangle/saw/sine from a VCO) within one period of the waveform. This leads to additional harmonics of the incoming signal. The period and consequently the pitch of the signals remains unchanged (in contrast to frequency multiplication e.g. with the PLL module A-196).

The A-137 works as a kind of "inverse low pass filter", i.e. it adds a lot of harmonics to a signal that contains none or only a few harmonics (e.g. sine or triangle waveform). In contrast to that a low pass filter removes harmonics from a signal that contains a lot of harmonics (e.g. saw or rectangle waveform). Consequently the best results are obtained in combination with input signals poor in harmonics (e.g. sine or triangle). The A-137 can be used with signals rich in harmonics too (e.g. saw) but the effect is not as remarkable as for triangle or sine waves. For rectangle signals none or only little effects are obtained. The A-137 is a very sophisticated wave multiplier that offers much more features, more controls and more waveform manipulations than other wave multipliers available so far. In addition all parameters are both manually adjusted and controlled by external voltages. The Multiples parameter (manual and ext. CV) defines the number of basic wave multiplications within one period. With the Folding Level and Symmetry parameter (both manual and ext. CV) the upper and lower clipping levels of the wave folder units are controlled. The Harmonics parameter (manual and ext. CV) adds some harmonic content by sharpening the waveform edges and adding overshoot peaks. It works a little bit like the resonance control of a VCF. The module is fully DC coupled, i.e. even control signal can be processed with the modules.

Merk:

Doepfer

Type:

Distortion, Waveshaper

Nummer:

A-137-1

Diepte:

65mm

Breedte:

14HP

Power:

40mA @ +12V, 20mA @ -12V

Module A-137-2 is another version of a wave multiplier. In contrast to the A-137-1 Wavemultiplier I the A-137-2 generates four phase-shifted copies of a VCO signal applied to the audio input. The four shifted signals are added to the original signal to obtain a fat sound similar to five independent VCOs. The phase shifting is made by a simple circuit that works only for sloped signals like sawtooth, triangle or sine, but not for rectangles or pulses.

Merk:

Doepfer

Type:

Distortion, Waveshaper

Nummer:

A-137-2

Diepte:

50mm

Breedte:

14HP

Power:

30mA @ +12V, 20mA @ -12V

Module A-138d can be used in two different ways:

• as a crossfader module within the A-100
• as an insert module for external effect units (e.g. guitar stomp boxes) with dry/wet control

If the module is used as a crossfader within the A-100 the two audio signals are connected to the sockets In 1 and In 2. The position of the CF (Crossfade) control defines the relation between the levels of the signals In 1 and In 2 that appear at the Mix Output. In the leftmost position of CF only In 1 appears at the output, in the rightmost position only In 2. In the center position both inputs appear with the same level at the Mix Output. Each input is equipped with two sockets (miniature multiples) so that the input signals can be forwarded to other modules too. Even the Mix Output has two sockets available. The mute switch can be used to mute In 1 or In 2 independent of the position of the crossfade control. In the center position it has no function. The controls Atten. and Amp. and the 1/4" sockets FX Send and FX Return are not used in this application. 

If the module is used as an effect send/return module with dry/wet control the A-100 signal that has to be processed by the external effect unit is connected to In 1. The signal can be attenuated by control Atten. before it is output to the 1/4" socket FX Send. The attenuator has been added because some effect units without input level control (especially guitar stomp boxes) will distort with A-100 levels (~ 1 Vss or more). The attenuator can be used to reduce the signal level so that no distortion occurs. Atten. is adjusted so that the external effect unit does not distort. The output of the external effect unit is connected to the 1/4" socket FX Return. This socket is followed by an amplifier and the control Amp. is used to amplify the signal to obtain again A-100 audio level (~ 1Vss or more). Amp is adjusted so that the loudness of both signals (i.e. original = dry = In 1 and the effect return signal = wet = In 2) have nearly the same loudness. The amplification range of the FX return amplifier is 1 to 50 (or  0 to 33dB). The output of the amplifier is normalled to the upper socket of Input 2. In this application no plug is inserted into the upper In 2 socket. The lower In 2 socket can be used to obtain the effect return signal before it is processed by the crossfade unit of the A-138d. The CF control of the A-138d works now as a dry/wet control for the external effect. In the leftmost position of CF only the original signal (i.e. not processed) appears at the Mix Output, in the rightmost position only the effect signal. In the center position the original and the processed signal appear with the same level at the Mix Output. The mute switch can be used to mute the original or the effect signal independent of the position of the crossfade control. In the center position it has no function.

Merk:

Doepfer

Type:

Insert, Panner, Crossfader

Nummer:

A-138d

Diepte:

40mm

Breedte:

8HP

Power:

20mA @ +12V, 20mA @ -12V

Module A-189-1 is a voltage controlled bit modifier. It offers several voltage controlled algorithmic functions like voltage controlled bit crunching, bit shifting (with/without carry over), bit exchange, rectifying, absolute value and calculating operations like addition, subtraction, multiplication or division.

The module has two control units both with manual control and CV input with attenuator:

• one for the algorithmic function according to the selected mode (e.g. number of shifted bits): BC and BC CV
• and one for the sampling rate (SR and SR CV)

The signal input is equipped with an attenuator. As the module is DC coupled even control voltages can be processed. The mode (e.g. bit crunching, bit shifting, bit exchange) is selected by a 16-position rotary switch:

1. Bit crushing: BC controls the number of bits (bit reduction)
2. AND: Signal AND BC
3. OR: Signal OR BC
4. XOR: Signal XOR BC
5. bit shift right: BC controls the number of bit shifts
6. bit shift left: BC controls the number of bit shifts
7. multiplication: Signal x BC
8. compare and complement: if signal > BC then output = bit complement of the input signal, otherwise unchanged
9. compare and absolute: if signal > BC then output = absolute value of the input signal, otherwise unchanged
10. addition: output = signal + BC (with overflow/clipping)
11. addition with BC swap: same as 10 but with nibble swap of BC (nibble = half byte, i.e. four bits)
12. short delay 1 with dynamic normalization: BC controls the length of the delay memory
13. short delay 2: same as 12 but different length/feedback
14. short delay 3: same as 12 but different length/feedback
15. short delay 4: same as 12 but different length/feedback
16. four stages FIR filter: BC controls the filter coefficient

Merk:

Doepfer

Type:

Bitcrusher

Nummer:

A-189-1

Diepte:

60mm

Breedte:

8HP

Power:

50mA @ +12V, 20mA @ -12V

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 similiar 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.

Merk:

Doepfer

Type:

Reverb

Nummer:

A-199

Diepte:

50mm

Breedte:

8HP

Power:

80mA @ +12V, 10mA @ -12V

The STEREO FX module brings hi-fi stereo effects into the Erica Synths Drum Series. Based on our new DSP engine, the module provides a wide range of custom delay and reverb effects. CV control over various parameters and the ability to save up to 10 presets will make this module an integral part of any performance rack.

Features

• Hi-Fi stereo FX module
• 3 delay and 3 reverb effects
• Tap and clock synchronization of delay time
• Delay time divisions and multiplications in sync mode
• 10 preset patches
• CV control over delay time, feedback, and preset selection

The FX is developed in collaboration with the Dutch company 112dB which offers some of the best-sounding VST instruments.

Merk:

Erica Synths

Type:

Drum/percussion, effect

Naam:

Drum Stereo FX

Diepte:

35mm

Breedte:

10HP

Power:

123mA @ +12V, 40mA @ -12V

Erica Synths Black Stereo Delay is a hi-fi stereo delay with a lot of unique features, based on our custom DSP engine. Tape, digital and ping-pong modes of delay, hold with overdub and delicate delay time and feedback control in combination with CV and trigger control over various parameters make this module not only great effects unit in your modular system but also - an instrument on its own.

Features

• Stereo delay with adjustable delay time
• Tape, digital and ping-pong delay modes
• Tap and clock synchronization of delay time
• Reverse delay mode
• Hold mode (samples up to 40” of audio) with Add (overdub) feature
• Trigger control over Hold, Add and Reverse
• CV control over delay time, dry/wet mix and feedback
• Feedback path soft limiting compression
• Add to hold soft limiting compression
• Adjustable stereo delay spread
• Firmware update via audio bootloader

Merk:

Erica Synths

Type:

Effect

Naam:

Black Stereo Delay2

Diepte:

37mm

Breedte:

16HP

Power:

162mA @ +12V, 62mA @ -12V

The Erica Synths Black Reverb is a versatile hi-fi stereo FX module with lots of unique features based on our custom DSP engine. The reverb sources are selectable Tape, BBD and "dirty BBD"; emulations with three modes, each – Room, Hall and Cathedral. Delicate room size control, feedback, tone and stereo spin controls allow for designing extremely delicate reverberation effects. CV control over various parameters and the ability to save up to 10 presets will make this module an integral part of any performance rack.

Features

• Reverb based on Tape, BBD and digital delay lines
• Three room sizes
• Manual and triggered FREEZE 
• 10 preset patches
• CV control over size, feedback, tone and preset selection
• Adjustable stereo spin

The modules run on new Erica Synths DSP hardware and the effects are developed in collaboration with Dutch company 112dB who make some of the most beautiful sounding effects.

Erica Black Series include high-end, unique functionality and superior quality modules. Only the best, highest-quality components are used, all inputs and outputs are protected against undesired overvoltage. Erica Black Series consist of range of modules that are needed to put together entire synth.

Merk:

Erica Synths

Type:

Effect

Naam:

Black Stereo Reverb

Diepte:

35mm

Breedte:

12HP

Power:

120mA @ +12V, 39mA @ -12V

Erica Synths Pico DSP is a smaller brother to the famous Black Hole DSP module. It features 8 custom effects with two adjustable parameters and CV control over the first parameter.

Features

• 8 great sounding stereo custom effects
• 2 adjustable parameters per effect
• CV control over the first parameter
• Dry/Wet control
• Stereo output
• Colour coded effects selection

Pico Series: is to possible to make ANY superior functionality synth module 3HP wide and affordable? Yes.

Merk:

Erica Synths

Type:

Effect

Naam:

Pico DSP

Diepte:

35mm

Breedte:

3HP

Power:

83mA @ +12V, 20mA @ -12V

The Black BBD is one of a kind analogue delay module - it features two BBD lines - short 1024 stage, and long 4096 stage that work simultaneously and you can smoothly fade between those two thus creating distinct multi-tap effect. Furthermore, an advanced BBD clock noise cancellation circuit is implemented that reduces unwanted BBD noise without filtering higher frequencies of the audio signal. Most of parameters are voltage controlled, which allows to integrate the module in complex modular setups.

Merk:

Erica Synths

Type:

Effect

Naam:

Black BBD

Diepte:

35mm

Breedte:

12HP

Power:

95mA @ +12V, 81mA @ -12V