Key (instrument) Key (instrument) A key is a specific part of a musical instrument. The purpose and function of the part in question depends on the instrument. On instruments equipped with tuning machines, violins and guitars, for example, a key is part of a tuning machine. It is a worm gear with a key shaped end used to turn a cog, which, in turn, is attached to a post which winds the string. The key is used to make pitch adjustments to a string. With other instruments, zithers and drums, for example, a key is essentially a small wrench used to turn
Electronic musical instrument Electronic musical instrument An electronic musical instrument is a musical instrument that produces sound using electronic circuitry. Such an instrument sounds by outputting an electrical, electronic or digital audio signal that ultimately is plugged into a power amplifier which drives a loudspeaker, creating the sound heard by the performer and listener. An electronic instrument might include a user interface for controlling its sound, often by adjusting the pitch, frequency, or duration of each note. A common user interface is the musical keyboard, which functions similarly to the keyboard on an acoustic piano, except that with an electronic keyboard, the keyboard