Control Voltage (CV)

What is control voltage?

Control Voltage is a DC electrical signal that is found in analog synthesizers. These signals are used to control the various components such as the oscillators, envelopes and filters.

In simple terms, more voltage produces a higher pitch and less voltage produces a lower pitch. Depending on how your analog is designed and what it allows to be modulated via CV, you can change the volume, attack, resonance, timbre and much more.

For example, you can manipulate the ADSR envelope and dictate how quickly the attack stage of a sound will take to reach its max volume, or how long the sustain stage will last. Another example would be the ability to control the gain on the VCA (voltage controlled amplifier).

Voltage control is a fundamental concept used in modular synthesizers and it is important to understand. In summary, if any module has a voltage-controlled parameter, then any other modules that can produce voltages will be able to control that parameter.

In modern synthesizers and keyboards, you can use voltage-controlled pedals that enables the musician to free up their hands for other uses. The volts are generated by a potentiometer that is able to read the information from the pedal and relay this into the synth to control parameters.