Music roll
From Wikipedia, the free encyclopedia
A music roll is a storage medium used to operate a mechanical organ, electronic carillon or orchestrion. Originally made of paper, modern rolls are sometimes made of thin plastic or PET film.
The music is stored by means of perforations. The mechanism of the instrument reads these as the roll unwinds, using a pneumatic sensing device called a tracker bar, and the mechanism subsequently plays the instrument.
After a roll is played, it is necessary for it to be rewound before it can be played again. This necessitates a break in a musical performance. To over come this, some instruments were built with two player mechanisms allowing one roll to play while the other rewinds. This increases the complexity of the instrument.
A piano roll is a specific type of music roll, and is designed to operate a player piano.
 Selecting a paper roll of music. |
 Music roll in place showing a pattern of holes representing notes. |
 Tracker bar, which reads the punched music roll. |
 Each hole is connected to a valve in the interior of the organ which operates the organ pipes such as these wooden ones. |
