Control voltage
From Just Solve the File Format Problem
In analog modular synthesizers, control voltage or CV is a method where cables transmit DC voltages that control parameters such as oscillator pitches, filter cutoffs, etc.
The exact input and output mappings are dependent on implementation. In the case of pitch, a common standard is the logarithmic scale of 1 volt per octave. Another sub-protocol of control voltage is a gate, where the CV crossing a certain threshold can be interpreted as a trigger or a note on/off event.
