12 inch

The twelve-inch single (often simply called a 12-inch or 12″) is a type of gramophone record that has wider groove spacing and shorter playing time compared to LPs. This allows for louder levels to be cut on the disc by the mastering 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 clubs. They are played at either 33 1⁄3 or 45 rpm.

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