Digital Recording

The first digital audio recorders were reel-to-reel decks introduced by companies such as Denon (1972), Soundstream (1979) and Mitsubishi. They used a digital technology known as PCM recording. Within a few years, however, many studios were using devices that encoded the digital audio data into a standard video signal, which was then recorded on a U-matic or other videotape recorder, using the rotating-head technology that was standard for video. A similar technology was used for a consumer format, Digital Audio Tape (DAT) which used rotating heads on a narrow tape contained in a cassette. DAT records at sampling rates of 48 kHz or 44.1 kHz, the latter being the same rate used on compact discs. Bit depth is 16 bits, also the same as compact discs. DAT was a failure in the consumer-audio field (too expensive, too finicky, and crippled by anti-copying regulations), but it became popular in studios (particularly home studios) and radio stations. A failed digital tape recording system was the Digital Compact Cassette (DCC).

Within a few years after the introduction of digital recording, multitrack recorders (using stationary heads) were being produced for use in professional studios. In the early 1990s, relatively low-priced multitrack digital recorders were introduced for use in home studios; they returned to recording on videotape. The most notable of this type of recorder is the ADAT. Developed by Alesis and first released in 1991, the ADAT machine is capable of recording 8 tracks of digital audio onto a single S-VHS video cassette. The ADAT machine is still a very common fixture in professional and home studios around the world.

In the consumer market, tapes and gramophones were largely displaced by the compact disc (CD) and a lesser extent the minidisc. These recording media are fully digital and require complex electronics to play back.

Interference colours on a compact disc.

Digital sound files can be stored on any computer storage medium. The development of the MP3 audio file format, and legal issues involved in copying such files, has driven most of the innovation in music distribution since their introduction in the late 1990s.

As hard disk capacities and computer CPU speeds increased at the end of the 1990s,hard disk recording became more popular. As of early 2005 hard disk recording takes two forms. One is the use of standard desktop or laptop computers, with adapters for encoding audio into two or many tracks of digital audio. These adapters can either be in-the-box soundcards or external devices, either connecting to in-box interface cards or connecting to the computer via USB or Firewire cables. The other common form of hard disk recording uses a dedicated recorder which contains analog-to-digital and digital-to-analog converters as well as one or two removable hard drives for data storage. Such recorders, packing 24 tracks in a few units of rack space, are actually single-purpose computers, which can in turn be connected to standard computers for editing.