Perforated paper music roll is a method of data storage, an information carrier consisting of a long strip of paper with holes punched in it.
Paper music roll as a musical media is primarily associated with the history of the mechanical piano and related instruments.

In the musical context, perforated roll is a program media that controls the complicated mechanism of a self-playing device (pianola or automatic piano). Each perforation in a musical perforated roll is a command to strike a specific note at a specific moment in time.

The standard width of a perforated roll for a pianola is about 28 cm. The roll length determines the musical piece duration (up to 20 minutes). The lines of transport holes (smaller diameter holes) are located along the roll edges. A tracker bar hooks onto them and pulls the roll evenly. This is the heart of the synchronisation mechanism. The main, central part of the roll surface is reserved for the notes’ holes. The roll width corresponds to the range of the piano keys (usually 88 notes). The position of a hole transversally the roll corresponds to a specific key on the instrument. The rightmost hole on the roll is the lowest, and the leftmost hole – is the highest one. The position along the band determines the moment when the note should be played.
The distance between the holes determines the rhythm and pauses. The further apart the holes are positioned, the longer is the pause between them. The magic of rolls is the possibility to encode nuances of performance. It's not just ‘on/off’ for a note. There are additional tracks on the roll to control the player piano mechanism: piano and forte tracks – two separate perforations on the edges of the note area. The ‘Forte’ hole made the mechanism strike the string harder; the ‘Piano’ hole made it strike softer. If neither was punched, the mechanism played at standard volume – ‘Mezzo'.
The sustain pedal was another service track that ‘pressed’ the pedal on the piano, allowing the notes to sound longer. The combined use of those control perforations made it possible to create truly expressive recordings, with crescendos, diminuendos and accents.
The device that reads such a roll and plays the music on a piano is called a pianola or automatic piano. Its mechanism is a masterpiece of pre-digital engineering.

The roll is loaded and pulled as follows: it is placed on the feeder; the transportation holes are placed on the tracker bar, which pulls the roll evenly at a constant speed. This speed determines the playback speed of the musical piece.

The reading unit is arranged as follows – vacuum reservoir (air chamber) connected to the tubes leading to each ‘finger’ of the mechanism is above the roll. A chamber with low pressure (created by foot pumps or, later, by electric motor) is underneath the roll. In other words, the principle of ‘pneumatic action’ is implemented. When a hole appears in the roll, it opens up access to air. Air from the vacuum chamber below is sucked through this hole into the upper chamber. This sudden flow of air activates a small pneumatic diaphragm connected to the piano hammer. The diaphragm inflates and pushes the hammer, which strikes the string. As soon as the hole passes further, the air flow stops, the diaphragm returns to its original position, and the hammer moves away from the string.
The control perforations (Forte/Piano) work on a similar principle; hence regulate the amount of air flow or the force of a strike.

Paper perforated roll in music was the analogue of audio recording for the time. It allowed the authentic performances of great pianists to be preserved; before the widespread distribution of gramophones and radio, it made possible to reproduce and play music at home, even the most complicated pieces.

The first mechanical piano with perforated roll, called “Pianista”, was manufactured in France in 1863. By 1885, the American company Mechanical Orguinette Company, which produced organettes, presented its version of a mechanical harmonium at an exhibition in London. Two years later, the company merged with the ‘Automatic Music Paper Co.’ and began mass production of harmoniums and perforated rolls for them. Almost simultaneously, another American company, ‘Wilcox and White’, began producing similar devices. At the turn of the 19^th-20^th centuries, recordings on perforated rolls became very popular all over the world.

The device with folded cardboard book-music was invented and patented by Italian piano builder Giovanni Racca in 1886. It consists of a 30-string sounding board with hammers controlled by moving perforated cardboard book-music. In 1888, Racca opened a factory for the production of mechanical pianos in Bologna, which produced these devices in virtually unchanged form until 1927, when they finally lost out to gramophones. The patents for the production of these devices were purchased by other prominent musical instrument manufacturers, such as Julius Heinrich Zimmermann (1851-1923), who had a shop in Moscow on Kuznetsky Bridge.

The separate area of development was the automation of other musical instruments: at the beginning of the 20^th century, mechanical violins, harps, banjos and entire orchestras appeared – orchestrions controlled by perforated rolls. Such devices became popular in cafes, dance halls, skating rinks and cinemas, where they were used during silent film screenings.

Production peaked in 1923, when companies released more than 250,000 mechanical pianos onto the market; in 1931, only 418 instruments were produced. The era of mechanical music was gradually coming to an end.

There were other applications for perforated rolls, such as in embroidery machines, typewriting and type-setting machines. But it is the telegraph and the mechanical piano that are the most spectacular examples of automation with the use of perforated rolls.

Perforated paper rolls produced by various companies at different periods of time are presented in the collection section ‘Music paper rolls and folded cardboardbook-music’. You can listen how they sound in the museum ‘Sound Library’.