Enharmonic keyboard

An enharmonic keyboard is a musical keyboard, where enharmonically equivalent notes do not have identical pitches. A conventional keyboard has, for instance, only one key and pitch for C♯ and D♭, but an enharmonic keyboard would have two different keys and pitches for these notes. Traditionally, such keyboards use black split keys to express both notes, but diatonic white keys may also be split.

As important device to compose, play and study enharmonic music, enharmonic keyboard may produce microtones and have separate keys for at least some pairs of not equal pitches that must be enharmonically equal in conventional keyboard instruments.

"Enharmonic keyboard" is a term used by scholars in their studies of enharmonic keyboard instruments (organ, harpsichord, piano,harmonium and synthesizer) with reference to a keyboard with more than 12 keys per octave. Scholarly consensus about the term's precise definition currently has not been established.

In the New Grove Dictionary (2001) Nicolas Meeùs defines an "enharmonic keyboard" as "a keyboard with more than 12 keys and sounding more than 12 different pitches in the octave". He however does not specify the origin of the term in his article. Rudolph Rasch (2002) suggested to apply the term "enharmonic keyboard" more closely to keyboards with 29–31 keys per octave.

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