player piano

Mechanical piano designed to reproduce key actions recorded on a perforated paper roll. The hammers are made to touch the strings not by action of the hand on the keyboard but by air pressure. This is regulated by a roll of perforated paper running over a series of slits corresponding with the musical scale and releasing the air only where the holes momentarily pass over the slits. The mechanism is set in motion by pedals like those of a harmonium.

Dynamics were at first controlled by the action of the players' hands, more or less roughly according to their skill, but they were later reproduced mechanically exactly as played by the recording artist. Debussy, Mahler, Grainger, and Stravinsky recorded their own works on piano roll. The concert Duo-Art reproducing piano encoded such detailed information that audiences were unable to distinguish a live performance from a reproduced performance. However, without a player, the player piano became simply a playback device for recordings, in which role it was superseded by the gramophone. In the 1950s–70s the US composer Conlon Nancarrow realized the instrument's potential for playing pieces that no human player could encompass – with strictly controlled tempo fluctuations, or extremely large numbers of notes – and produced his Etudes for player piano.

In 1986 the Viennese firm Bösendorfer produced an instrument which, it is claimed, can reproduce every nuance of a performance. Optical sensors scan the keys, hammers, and pedals 800 times per second and the registered information is fed into a computer. It is stored on tape or floppy disk and can be relayed back to the piano for ‘performance’.