Keyboard instrument

A keyboard instrument is a musical instrument played using a keyboard. The most common of these are the piano, organ, and various electronic keyboards, including synthesizers and digital pianos. Other keyboard instruments include celestas, which are struck idiophones operated by a keyboard, and carillons, which are usually housed in bell towers or belfries of churches or municipal buildings.

Today, the term keyboard often refers to keyboard-style synthesizers. Under the fingers of a sensitive performer, the keyboard may also be used to control dynamics, phrasing, shading, articulation, and other elements of expression—depending on the design and inherent capabilities of the instrument.

Another important use of the word keyboard is in historical musicology, where it means an instrument whose identity cannot be firmly established. Particularly in the 18th century, the harpsichord, the clavichord, and the early piano were in competition, and the same piece might be played on more than one. Hence in a phrase like "Mozart excelled as a keyboard player" the word keyboard is usefully noncommittal.

The earliest known keyboard instrument was the Ancient Greek hydraulis, a type of pipe organ, invented in the third century BC. The keys were likely balanced and could be played with a light touch, as is clear from the reference in a Latin poem by Claudian (late 4th century), who says magna levi detrudens murmura tactu . . . intent, that is “let him thunder forth as he presses out mighty roarings (shifa) with a light touch” (Paneg. Manlio Theodoro, 320–22). From its invention until the fourteenth century, the organ remained the only keyboard instrument. Often, the organ did not feature a keyboard at all, but rather buttons or large levers operated by a whole hand. Almost every keyboard until the fifteenth century had seven naturals to each octave.

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