New Doepfer Modules Coming to SUPERBOOTH

Avialable in black and silver.

Module A-121s is a dual multimode filter which can be used for stereo applications as well as for parallel or serial organized dual mono filters. The core is a 12dB multimode filter identical to the modules A-121-2 and A-121-3. The selection of the filter type is continuously from lowpass via notch and highpass to bandpass. We attached great importance to the usability of the manual controls and CV inputs for both stereo and dual mono applications. For the filter parameters frequency (F), resonance (Q) and type (T) common controls and CV inputs as well as single controls and CV inputs are available. For the filter frequency in addition a manual control and CV input for the filter spread (frequency difference or delta F) is available.

Controls:

F: master frequency control for both filters (large knob)
Type 1 / Type 2: filter type panning/morphing L-N-H-B
Link to 1: Toggle switch so that Type 1 also controls type of filter 2 (i.e. simultaneous filter type control for both filters)
SFM1 / SFM2: Single Frequency Modulation controls (polarizers), connected to the corresponding sockets SFM1/SFM2 (socket SFM1 is normalled to a fixed positive voltage, SFM2 is normalled to SFM1, that way the controls SFM1/SFM2 work as frequency controls for each filter provided that no modulation signals are patched to the SFM1/SFM2 sockets)
CFM: common frequency control, controls two VC-polarizers which process the signals connected to the two sockets CFM1/CFM2, CFM2 is normalled to CFM1, that way also the same modulation signal (e.g. an envelope generator) can be used for both filters and the level controlled simultaneously by the CFM control
Delta F: controls the difference between the frequencies of the two filters manually (frequency "spread"), at center position the frequencies are the same
Delta FM: controls the level of the Delta FM signal (socket), which allows to control the spread between the frequencies also by an external control voltage (e.g. by an LFO or ADSR)
Q: controls the resonance of both filters simultaneously
Level 1 / Level 2: attenuators for the two audio inputs
QM/TM1, QM/TM2: attenuators for the modulation inputs QM/TM1 and QM/TM2
Sockets:

In1 / In2: audio inputs (In2 is normalled to In1)
Out1 / Out2: audio outputs
F: common frequency control input for both filters (~ 1V/oct)
Delta FM: Control voltage for frequency spread, processed by the polarizer Delta FM
SFM1 / SFM2: single frequency modulation inputs, processed by the polarizers SFM1 and SFM2, SFM1 is normalled to a fixed positive voltage, SFM2 is normalled to SFM1#
CFM1 / CFM2: common frequency modulation inputs, processed by the two voltage controlled polarizers controlled by CFM knob, CFM2 is normalled to CFM1
QM/TM1, QM/TM2: the addressing of these sockets/attenuators is defined by internal jumpers. QM means Q modulation (i.e. resonance modulation), TM means filter type modulation (QM1 = resonance modulation filter 1, QM2 = resonance modulation filter 2, TM1 = filter type modulation filter 1, TM2 = filter type modulation filter 2), socket QM/TM1 is normalled to a fixed positive voltage, QM/TM2 is normalled to QM/TM1
A 45 degrees triangle next to a socket means that the switching contact of the socket is normalled to a fixed positive voltage.
A vertical triangle indicates the normalling of two sockets.

By means of small circles at the bottom right side of the front panel the user can mark the function of the QM/TM inputs. These assignments are possible:

QM/TM1 controls QM1, QM/TM2 controls QM2, the filter types are not controlled by external CVs
QM/TM1 controls TM1, QM/TM2 controls TM2, the resonances are not controlled by external CVs
QM/TM1 controls QM1 and QM2 simultaneously, QM/TM2 controls TM1 and TM2 simultaneously
Applications:
Stereo filter: two different audio signals are connected to the audio inputs. At the outputs appear the filtered signals. The filterings depend upon the positions of the manual controls and the applied control voltages.
Serial mono filter: the mono signal is applied to audio input 1. Audio output 1 is connected to audio input 2. The filtered mono signal appears at audio output 2. One has to pay attention that the filter parameters are set in a way so that a signal will appear at the output. If for example a lowpass and a highpass are daisy chained the frequency of the lowpass has to be higher than the frequency of the highpass. Otherwise no signal will appear at the output.
Parallel mono filter: the audio signal is fed to both audio inputs (e.g. via the normalled sockets In1>In2). By means of a mixer module the audio outputs 1 and 2 are mixed.
The sketch below shows the internal structure of the module in detail.

Release date: about June 2022 (without obligatiion)
All specifications are still preliminary and without obligation !

Module A-138j is a four channel mixer with an additional polarity/mute switch for each input. In the upper position of the corresponding switch the inverted signal is used. In the center position the input in question is turned off (mute) and in the lower position the "normal" (i.e. non-inverted) signal is used. The inverting of signals is used especially for control voltage signals (e.g. LFO, ADSR). But even for corellated audio signals this feature is useful. For example for feedback applications or the mixing of original and processed signals (e.g. original and filtered signal to obtain new filter types).
On top of that the module is equipped with two types of single outputs and a dual mix output. All inputs and outputs are DC coupled. Consequently the VCAs can be used to mix both audio and control voltages.
Each input is - apart from the polarity/mute switch - equipped with a linear attenuator. The amplification range is 0....1.
The single outputs offer the attenuated and possibly inverted/muted signal of the channel in question. Two version of single outputs are available:

Single Output A: If a plug is inserted into the single output "A" socket the channel in question is removed from the sum signal.
Single Output B: If a plug is inserted into the single output "B" socket the channel in question is not removed from the sum signal. This type of single outputs is available only for the channels 1 and 2.
The output is twice available (two sockets, hard-wired like a multiple).

The distances between the controls and sockets are smaller as for the standard A-100 modules and rubberized small-sized knobs are used. In return the front panel has 6 HP width only. The module is primarily planned for applications where only limited space is available.

Release date: about July 2022 (without obligatiion)
All specifications are still preliminary and without obligation !

Module A-183-5 is a simple passive quad attenuator. Passive means in this context, that each unit is made of two sockets and a 50k linear potentiometer only. There are no active parts like amplifiers or buffers and no power supply is required.
This is how the A-183-5 works: At the output socket appears the attenuated input signal, i.e. zero level at the fully CCW position and max. level and the fully CW position.

Applications:
Adjustable level of CV or audio signals to control other modules that do not have attenuators available.

Release date: about July 2022 (without obligatiion)
All specifications are still preliminary and without obligation !

schematics of one A-183-5 unit