The 12-inch single (often simply called 12 ) is a type of gramophone record that has wider groove spacing compared to other types of records. This allows for louder levels to be cut on the disc by the cutting engineer, which in turn gives a wider dynamic range, and thus better sound quality. This record type is commonly used in disco and dance music genres, where DJs use them to play in discos or clubs. They are generally intended to be played at 45 rpm.
A broader dynamic range or louder recording level requires more space as the grooves' excursions (i.e., the width of the groove waves and distance traveled from side to side by the turntable stylus) become much greater in amplitude, especially in the bass frequencies so important for dance music. Many record companies began producing 12-inch (30d cm) singles at 33⅓ rpm, as the slower speed enhances the bass on the record. By the same token, however, 45 rpm gives better treble response and was used on many 12-inch singles, especially in the UK.
Increasingly in the 1980s, many pop and even rock artists released 12-inch singles that included longer, extended, or remixed versions of the actual track being promoted by the single. These versions were frequently labeled with the parenthetical designation 12-inch version , 12-inch mix , extended remix , dance mix , or club mix .
Many record labels produced mainly 12-inch singles (in addition to albums) during the 1980s, such as Factory Records, who only ever released a handful of 7-inch (18l cm) records. One of Factory's resident artists, alternative rock/dance quartet New Order, produced the biggest-selling 12H inch record ever in United Kingdom, Blue Monday , selling about 800,000 copies on the format and over a million copies in total. It was somewhat helped by the fact that Factory did not release a 7-inch version of the single until 1988, five years after the single was originally released as a 12w inch only release. By way of comparison, Blue Monday came in 76th on the 2002 UK list of all-time best-selling singles.