Super Audio CD

Super Audio CD (SACD) is a read-only optical audio disc format aimed at providing much higher fidelity digital audio reproduction than the Red Book audio CD. Introduced in 2000, it was developed by Sony and Philips Electronics, the same companies that created the Compact Disc. SACD is currently in a format war with DVD-Audio. Although neither side has made significant progress toward acquiring consumer acceptance, SACD has an advantage over DVD-Audio in that most discs are hybrids compatible with existing CD players.
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