Tube VCA is based on soviet tube - beam tetrode 2П2П. Datasheet. The tube is designed to amplify the power of low frequency. The tube is used in battery-powered audio amplifiers (low-voltage).
FEATURES:
CV controls control voltage input level. 5 Volts CV covers whole GAIN range.
GAIN controls amplifier gain offset.
DRIVE/IN1 controls IN1 level
FEEDB/IN2 controls IN2 level, or if nothing feeded into IN2 controls feedback loop level.
CLIP switch switches the device between two modes: NEG where it clips more negative half of a signal, POS where it clips more positive half of a signal. Asymmetrical or non-linear distortion.
Easy to swap the Tube if broken. No soldering there - headers and screws.