A player piano is a mechanically operated piano, especially a pedal-operated or motor-driven piano using pneumatic suction to move the keys in correspondence to the perforations on a turning piano roll. [American Heritage Dictionary].
The earliest known player pianos date back to the 1500s when piano builder Samuel Bidermann of Augsburg, Germany equipped three spinets (small, upright pianos) with pinned barrels similar to those in music boxes during his lifetime from 1540 to 1622. However, it wasn't until the end of the 19th century that interest in self-playing pianos was revived. In the early 1900s, standardization of the paper rolls created an industry for the manufacture of player pianos.
By the early 1920s, the player piano had reached its peak and at one point more than half of all pianos being made in America contained a player unit. However, advances in radio technology as well as electrical recording systems such as amplification for 78 rpm records, contributed to the decline of the player piano's popularity. When the stock market crashed in 1929, only a few player piano companies were able to continue, many through consolidation of smaller companies.
In the 1950s and 1960s, a number of collectors began to rescue player pianos and piano rolls and to form societies dedicated to peserving all forms of mechanical music. By the 1960s, production of player pianos had been revived as well as the rebuilding of original instruments which continues today.
A piano roll itself consists of a continuous sheet of paper rolled onto a spool, though modern rolls are often made of thin plastic or polyester film. The music to be played is programmed onto the paper by means of perforations. The spool fits into the player piano spool box, and the instrument's reading mechanism, the tracker bar, reads these as the roll undwinds. After a roll is played, it is necessary for it to be rewound before it can be played again. As of 2011, QRS Music claims to be the only manufacturer of music rolls in the world today with over 5,000 master recordings and over 45,000 music rolls.