“CV/Gate” is an abbreviation for “Control Voltage/Gate,” which refers to a common method of controlling and triggering synthesizers, particularly analog and modular synthesizers, using two separate electrical signals:
- Control Voltage (CV): As previously explained, CV is a continuous electrical signal that is used to modulate various parameters of a synthesizer, such as pitch, filter cutoff, or modulation depth. In the context of CV/Gate, the primary use of CV is for controlling the pitch of an oscillator. The voltage level of the CV signal corresponds to a specific pitch, usually following the 1 volt per octave (1V/Oct) standard, where an increase of 1 volt results in a pitch increase of one octave.
- Gate: The Gate signal is a simple on/off or high/low signal used to trigger events in a synthesizer, such as initiating an envelope generator, starting or stopping a sequencer, or activating a voice in a polyphonic synthesizer. When a Gate signal is high (e.g., +5V), it typically indicates that a note is being played, and when it is low (e.g., 0V), it indicates that the note has been released. The duration of the high state corresponds to the length of the note being played.
CV/Gate is a widely used method for interfacing different synthesizers, sequencers, or controllers, allowing them to communicate pitch and note-on/note-off information. In modular synthesizers, CV/Gate signals are routed between modules using patch cables, while in other synthesizer systems, CV/Gate signals may be transmitted via dedicated connections, such as 1/4-inch or 3.5mm jacks, or even specialized interfaces like the Roland 24-pin DIN connector used in their early analog synthesizers.
With the advent of digital synthesizers and MIDI (Musical Instrument Digital Interface), the use of CV/Gate has become less prevalent in modern synthesizer designs, but it remains popular in the world of analog and modular synthesizers due to its simplicity, hands-on approach, and compatibility with a wide range of vintage and contemporary gear.