DVD-Audio (DVD-A) is a Digital Versatile Disc (DVD) format, developed by Panasonic, that is specifically designed to hold audio data, and particularly, high-quality music. The DVD Forum, consisting of 230 leading companies worldwide, released the final DVD-A specification in March of 1999. The new DVD format is said to provide at least twice the sound quality of audio CD on disks that can contain up to seven times as much information. Various types of DVD-A-compatible DVD players are being manufactured, in addition to the DVD-A players specifically developed for the format.
Almost all of the space on a DVD video disc is devoted to containing video data. As a consequence, the space allotted to audio data, such as a Dolby Digital 5.1 soundtrack, is severely limited. A lossy compression technique - so-called because some of the data is lost - is used to enable audio information to be stored in the available space, both on standard CDs and DVD-Video disks. In addition to using lossless compression methods, DVD-A also provides more complexity of sound by increasing the sampling rateand the frequency range beyond what is possible for the space limitations of CDs and DVD-Video. DVD-Audio is 24-bit, with a sampling rate of 96 kHz; in comparison, DVD-Video soundtrack is 16-bit, with a sampling rate of 48 kHz, and standard audio CD is 16-bit, with a sampling rate of 44.1 kHz.
Although DVD-A is designed for music, it can also contain other data, so that - similarly to Enhanced CD - it can provide the listener with extra information, such as liner notes and images. A variation on the format, DVD-AudioV, is designed to hold a limited amount of conventional DVD video data in addition to DVD-Audio. DVD-A is backed by most of the industry as the technology that will replace the standard audio CD. The major exceptions are Philips and Sony, whose Super Audio CD (SACD) provides similar audio quality. Like DVD-A, SACD offers 5.1 channel surround sound in addition to 2-channel stereo. Both formats improve the complexity of sound by increasing bit rates and sampling frequencies, and can be played on existing CD players, although only at quality levels similar to those of traditional CDs.