Super Audio CD

Super Audio CD (SACD) is a read-only optical disc for audio storage, introduced in 1999. It was developed jointly by Sony and Philips Electronics, and intended to be the successor to their Compact Disc format. The SACD format can offer more channels (e.g. surround sound), and a longer playing time than CD. Researchers have disputed the claim that SACD offers sound quality significantly different from a standard CD.

Having made little impact in the consumer audio market, by 2007 SACD was deemed to be a failure by the press. In the 2010s, a small market for SACD remains, serving the audiophile community.