A-131 Exponential VCA

Doepfer's exponential VCA, meant above all for audio: two audio inputs mixed, amplified by the sum of two CVs and the Gain control, with an output level control.

Key features

• Exponential voltage controlled amplifier (the A-130-1 is its linear twin, for control voltages)
• Gain is summed with CV1 and CV2: the VCA opens by hand without any CV
• CV1 and CV2 take about 0 to +5 V for a gain of 0 to 1; CV2 has an attenuator
• Two audio inputs, each with its level control (In1, In2), summed into the VCA
• Out sets the output level