Doepfer A-132-4 Quad Exponential VCA/Mixer

Doepfer A-132-4 Quad Exponential VCA/Mixer The control scale for each VCA is about 12dB/V (i.e. 1 V CV decrease corresponds to 12dB level decrease and 1 V CV inrease corresponds to 12dB level increase). 0V CV corresponds to about -60dB (i.e. about attenuation by 1000). +5V CV corresponds to about 0dB (i.e. no attenuation or amplification = 1). The full attenuation/amplification range is about -90dB ... + 20dB. Attenuations below -60dB require a negative control voltage, amplifications beyond 0dB require a control voltage more than +5V. For the first CV input of each unit (CV1) an internal trimming potentiometer (attenuator) is available to adjust the control scale for other voltage ranges (e.g. 0...+8V for A-140 envelope control or 0...+10V for external 10V control voltages). To obtain another CV scale even for CV2 an attenuator (e.g. A-183-1) can be used. If an amplification offset is required (e.g. for zero-symmetrical control voltages like LFO) an external offset generator with attenuator/polarizer (e.g. A-183-2) is recommended.