In electronic music, a pitch wheel is a control on a synthesizer to pitch bend (portamento) — to vary the pitch in a continuously variable manner.
The first synthesizer with a pitch wheel was the Minimoog, in 1970.
In the MIDI specification, the pitch wheel may send 16,384 possible variation values. The General MIDI specification recommends that the total range be ± 2 semitones.[1] Pitch bend range is General Midi Registered Parameter Number 0, 0.