Sonosheet

The flexi disc (also known as a phonosheet, Sonosheet or Soundsheet, a trademark) is a phonograph record made of a thin, flexible vinyl sheet with a molded-in spiral stylus groove, and is designed to be playable on a normal phonograph turntable. Flexible records were commercially introduced as the Eva-tone Soundsheet in 1962, and were very popular among children and teenagers and mass-produced by the state publisher in the Soviet government.

Before the advent of the compact disc, flexi discs were sometimes used as a means to include sound with printed material such as magazines and music instruction books. A flexi disc could be moulded with speech or music and bound into the text with a perforated seam, at very little cost and without any requirement for a hard binding. One problem with using the thinner vinyl was that the stylus's weight, combined with the flexi disc's low mass, would sometimes cause the disc to stop spinning on the turntable and become held in place by the stylus. For this reason, most flexi discs had a spot on the face of the disc for a coin, or other small, flat, weighted object to increase the friction with the turntable surface and enforce consistent rotation. If the turntable's surface is not completely flat, it is recommended that the flexi disc be placed on top of a full sized record.

In Japan, starting in the early 1960s, Asahi Sonorama published the monthly Asahi Sonorama magazine which included an inserted flexi disc ("Sonosheet").

Every year between 1963 and 1969, The Beatles made a special Christmas recording which was made into a flexi disc and sent to members of their fan club. While the earlier discs largely contained 'thank you' messages to their fans, the later Christmas flexis were used as an outlet for the Beatles to explore more experimental areas; the 1967 disc, for example, became a pastiche of a BBC Radio show and even included a specially recorded song entitled "Christmas Time (Is Here Again)."

In 1964, the National Geographic Society released Song and Garden Birds of North America which included a 12-sided clear flexidisk, bound alternating with pages giving the titles and birds on the recordings. The work was done by Arthur A. Allen and Peter Paul Kellogg of the Cornell Laboratory of Ornithology.

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