Doepfer A-178V Eurorack Theremin CV Source Module (Black)

Theremin module for generating a variable control voltage by approaching/removing hand to/from an antenna. The distance range is about 30-40 cm. Additionally the module is equipped with a Gate output with adjustable threshold level. Controls/Inputs/Outputs: antenna input, offset (knob for zero adjust), 2 x CV out, 2 x LED (for CV control positive/negative and zero offset adjust)
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.

Applications:

• controlling any voltage controlled parameter of the A-100, e.g. pitch or pulswidth (VCO A-110), loudness (VCA A-130/131/132), panorama (A-134), filter frequency or resonance (A-120/121/122/123), phasing (A-125), frequency shift (A-126), resonance peaks (A-127), envelope parameters (A-141/142), tempo (A-147)
• triggering of A-100 activities via gate with adjustable threshold, e.g. starting an envelope (A-140/141/142), Start/Stop of a sequence (A-155), any switching function (A-150/151)

Remark: If two or more A-178 are used the distance between the modules/antennas should be at least 40-50 cm. Otherwise the antennas may affect each other.

Technical Notes:

It's not possible to connect the antenna via an additional cable to the antenna socket or to replace the antenna by another element. Antenna and hand form a variable capacitor with a very small capacity in the pico Farad range. The electronics of the module is puzzled out just for this capacity range. If a cable is added or the antenna is replaced by another element the capacity range changes totally and the module will no longer work !