The 4VCA 31B is 4 individual high quality low noise linear Class A VCAs on a single panel. The 4VCA is also an excellent voltage controlled 4 x 1 sub-mixer for both audio and DC voltage control. An essential module for medium to large systems.

AC mode: the VCA inputs are capacitor coupled for minimum offset feed through to reduce 'thumping' with sharp attacks on audio signals.

DC mode:the VCA inputs are direct coupled to the VCAs for processing control voltages and clocks/gates etc.

The four VCAs are normalled to the Mix output for combining all 4 channels to one output. Inserting a plug into the individulal VCA outputs breaks the connection removing it from the mix.
Example: Mix two channels of audio while using the other two for CV processing.

  • Features:
  • 4 VCAs with separate panel controls, attenuators and CV inputs
  • Low noise SSM2164 VCA ICs
  • 75-80dB of control range
  • Linear response
  • Mix out for all 4 VCAs combined

Specs:
4 Class A VCAs
Input/Output: 0-20V P-P
CV input: 0-5V
75-80 dB control range
Linear response
Outputs: 1k ohms
Inputs: 100k ohms

Current Requirements:
70mA@+15V
65mA@-15V