Electronic musical instrument

An electronic musical instrument is a musical instrument that produces sound using electronics. Such an instrument sounds by outputting an electrical audio signal that ultimately drives a loudspeaker.

An electronic instrument might include a user interface for controlling its sound, often by adjusting the pitch, frequency, or duration of each note. However, it is increasingly common to separate user interface and sound-generating functions into a music controller (input device) and a music synthesizer, respectively, with the two devices communicating through a musical performance description language such as MIDI or Open Sound Control.