The Doepfer A-131 Exponential VCA provides voltage-controlled amplification for audio signals (though can work for CV too). The amount of amplification the VCAs provide is determined by the voltage at the CV input, and the position of the gain control, which sets the overall gain in the system.

The VCA has two audio inputs, each with an attenuator. They are amplified by an amount determined by the combination of the gain and the two CV controls.

Key Features:

Width: 8 HP / 40.3 mm
Depth: 45 mm
Current: +20mA (+12V) / -10mA (-12V)