Music keyboard

A musical keyboard is the set of adjacent depressible levers or keys on a musical instrument. Keyboards typically contain keys for playing the twelve notes of the Western musical scale, with a combination of larger, longer keys and smaller, shorter keys that repeats at the interval of an octave. Depressing or striking a key on the keyboard makes the instrument produce sounds, either by making a hammer mechanically strike a string or metal tine (piano, electric piano, clavichord); pluck a string (harpsichord); open a valve to let air flow through a pipe (pipe organ or accordion); or strike a bell (a carillon in a church tower). On electric and electronic keyboards, depressing a key connects one or more circuits (Hammond organ, digital piano, synthesizer, MIDI controller keyboard), which triggers a musical sound. A pedal keyboard is a keyboard played with the feet, usually used with a pipe organ or theatre organ. Since the most commonly encountered keyboard instrument is the piano, the keyboard layout is often referred to as the "piano keyboard".

Musical keyboards can have as few as 12 keys, as in the case of the pedal keyboards used with spinet organs and some small bass synthesizers, 25 keys for small, 2010-era MIDI controller keyboards, 61 keys for many inexpensive home keyboards, 73 keys for professional electronic keyboards and 88 keys for an acoustic piano. Some keyboards have two "ranks" of keyboards, one stacked above the other, with the two keyboards referred to as the lower and upper manual, such as the Hammond organ, pipe organs and some harpsichords. Some pipe organs and theatre organs may have three keyboards. Keyboards that have multiple manuals typically give the player the option of using different "registrations" or sounds for each keyboard. Pedal keyboards have from 12 keys (home spinet organs) to 25 keys (many Hammond organs) to 32 or more (pipe organs in churches).

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Wikipedia