LP record
The LP (from "long playing" or "long play") is an analog sound storage medium, a phonograph record format characterized by: a speed of 33+1⁄3 rpm; a 12- or 10-inch (30- or 25-cm) diameter; use of the "microgroove" groove specification; and a vinyl (a copolymer of vinyl chloride acetate) composition disk. Introduced by Columbia Records in 1948, it was soon adopted as a new standard by the entire US record industry. Apart from a few relatively minor refinements and the important later addition of stereophonic sound in 1957, it remained the standard format for record albums, during a period in popular music known as the album era. Beginning in the late 1970s, LP sales began to decline because of the increasing popularity of Compact Cassettes, then in the 1980s of compact discs. By 1988, the latter format began to outsell LPs.
A 12-inch LP vinyl record | |
Media type | Audio playback |
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Encoding | Analog groove modulation |
Capacity | Originally 23 minutes per side, later increased by several minutes, much longer possible with very low signal level |
Read mechanism | Microgroove stylus (maximum tip radius 0.001 in or 25 μm) |
Developed by | Columbia Records |
Dimensions | 12 in (30 cm), 10 in (25 cm), 90–240 g (3.2–8.5 oz) |
Usage | Audio storage |
Released | 1948 |
Beginning in the late 2000s, the LP has experienced a resurgence in popularity. 2020 was the first year when vinyl outsold CDs in the US, making up 62% of all physical music revenue.