Pianola

A player piano (also known as pianola) is a self-playing piano, containing a pneumatic or electro-mechanical mechanism that operates the piano action via pre-programmed music recorded on perforated paper, or in rare instances, metallic rolls, with more modern implementations using MIDI. The rise of the player piano grew with the rise of the mass-produced piano for the home in the late 19th and early 20th century. Sales peaked in 1924, then declined as the improvement in phonograph recordings due to electrical recording methods developed in the mid-1920s. The advent of electrical amplification in home music reproduction via radio in the same period helped cause their eventual decline in popularity, and the virtually wiped out production.

The idea of automatic musical devices can be traced back many centuries, and the use of pinned barrels to operate percussion mechanisms (such as striking bells in a clock) was perfected long before the invention of the piano. These devices were later extended to operate musical boxes, which contain a set of tuned metal teeth plucked by the player mechanism.

An early musical instrument to be automated was the organ, which is comparatively easy to operate automatically. The power for the notes is provided by air from a bellows system, and the organist or player device only has to operate a valve to control the available air. The playing task is ideally performed by a pinned barrel, and the art of barrel organs was well advanced by the mid-18th century.

The piano is a complex instrument, requiring each note to be struck with a different force to control the dynamics of the performance. The entire force required to sound the note must be given by the performer hitting the keys. It proved to be difficult for a player device to combine a variable percussive force and a controlled note duration. Barrels do not provide a percussive force, but a relatively gentle switching motion.

Early barrel pianos moved the hammer back and forwards continuously as the operator turned the handle, but the hammers did not strike the strings until moved slightly forwards by a pin in the barrel. The hammers hit repeatedly until the pin was removed. This played the note, but at a fixed dynamic and with a tremolo action quite unlike a pianist.

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Wikipedia