Music in Digital Media Developing technologies and how these have shaped popular music production…

Introducing digital audio… Digital audio refers to technology that records, stores, and reproduces sound by encoding an audio signal in digital form instead of analogue form. Digital audio systems may include compression, storage, processing and transmission components. Conversion to a digital format allows convenient manipulation, storage, transmission and retrieval of an audio signal.

Developing technologies… Sony developed the first digital audio recording devices to be used by professional studios in 1978. The next year, Sony revolutionized the world of personal audio with the introduction of the Walkman portable audio cassette player, initially called the “Soundabout.” Though compact disc technology emerged the following year, Sony went on to sell over 100 million Walkman-like audio players—and that was in addition to innumerable knock-offs by other manufacturers, even before personal audio players evolved to play digital mediums such as compact discs (1988) and minidiscs (1992). The first commercially available digital audio players in the United States using the MP3 format (which had been in development since 1987) would launch the digital audio player revolution that achieved meteoric success with the introduction of Apple’s iPod in 2001 (Holmes 2006).

Digital Audio Tape (DAT) (DAT or R-DAT) is a signal recording and playback medium developed by Sony and introduced in 1987.[1] In appearance it is similar to a Compact Cassette, using 4 mm magnetic tape enclosed in a protective shell, but is roughly half the size at 73 mm × 54 mm × 10.5 mm DAT has the ability to record at higher, equal or lower sampling rates than a CD (48, 44.1 or 32 kHz sampling rate respectively) at 16 bits quantization. If a digital source is copied then the DAT will produce an exact clone, unlike other digital media such as Digital Compact Cassette or non-Hi-MD MiniDisc, both of which use a lossy data reduction system. Although intended as a replacement for audio cassettes, the format was never widely adopted by consumers because of issues of expense and concerns from the music industry about unauthorized digital quality copies. The format saw moderate success in professional markets and as a computer storage medium. The technology of DAT is closely based on that of video recorders, using a rotating head and helical scan to record data. This prevents DATs from being physically edited in the cut-and-splice manner of analog tapes, or open-reel digital tapes like ProDigi or DASH.

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Compact Disc (CD) The compact disc, or CD for short, is an optical disc used to store digital data. The format was originally developed to store and play back sound recordings only (CD- DA), but was later adapted for storage of data (CD-ROM). Audio CDs and audio CD players have been commercially available since October 1982. At the time of the technology's introduction it had more capacity than computer hard drives common at the time. The reverse is now true, with hard drives far exceeding the capacity of CDs. The Compact Disc is an evolution of LaserDisc technology. Prototypes were developed by Philips and Sony independently from the mid-to-late 1970s. The two companies then collaborated to produce a standard format and related player technology which was made commercially available in 1982. In 1974, an initiative was taken by L. Ottens, a director of the audio industry group within the Philips Corporation in Eindhoven, the Netherlands. A seven-person project group was formed to develop an optical audio disc with a diameter of 20 cm with a sound quality superior to that of the large and fragile vinyl record. Later in 1979, Sony and Philips set up a joint task force of engineers to design a new digital audio disc. First published in 1980, the standard was formally adopted by the IEC as an international standard in 1987, with various amendments becoming part of the standard in 1996.

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Digital Compact Cassette (DCC) DCC is a magnetic tape sound recording format introduced by Philips and Matsushita in late 1992 and marketed as the successor to the standard analogue Compact Cassette. DCC was envisaged as a cheaper alternative to DAT. DCC shared a similar form factor to analogue cassettes, and DCC recorders could play back either type of cassette. This backward compatibility allowed users to adopt digital recording without rendering their existing tape collections obsolete. DCC signalled the parting of ways of Philips and Sony, who had worked together successfully on the Compact Disc, CD-ROM and CD-i before. Based on the success of Digital Audio Tape in professional environments, both companies saw a market for a new consumer-oriented digital audio recording system that would be less expensive and perhaps less fragile. DCC was developed in cooperation with Matsushita, and the first DCC recorders were introduced at the Firato consumer electronics show in Amsterdam in 1992. DCC used a Magneto-Resistive (MR) head, which was fixed to the mechanism of the player/recorder, unlike rotary heads that are used in helical scan systems such as DAT or VHS to increase head-to-tape speed

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MiniDisc (MD) MiniDisc was announced by Sony in September 1992 and released that November for sale in Japan and in December for the USA and Europe. The music format was originally based exclusively on ATRAC audio data compression, but the option of linear PCM digital recording was later introduced to attain audio quality comparable to that of a compact disc. MiniDiscs were very popular in Japan but made a limited impact elsewhere. MD Data, a version for storing computer data, was announced by Sony in 1993 but never gained significant ground. Its media were incompatible with standard audio MiniDiscs, which has been cited as one of the main reasons behind the format's failure. MiniDisc has a feature that prevents disc skipping under all but the most extreme conditions. Older CD players had once been a source of annoyance to users as they were prone to mistracking from vibration and shock. MiniDisc solved this problem by reading the data into a memory buffer at a higher speed than was required before being read out to the digital-to-analogue converter at the standard rate required by the format. The size of the buffer varies by model. The data structure and operation of a MiniDisc is similar to that of a computer's hard disk drive. The bulk of the disc contains data pertaining to the music itself, and a small section contains the Table of Contents. Tracks and discs can be named, and may easily be added, erased, combined and divided, and their preferred order of playback modified. Erased tracks are not actually erased at the time. When a disc becomes full, the recorder can simply slot track data into sections where erased tracks reside

DVD-Audio (DVD A) DVD-Audio offers many possible configurations of audio channels, ranging from single- channel mono to 5.1-channel surround sound, at various sampling frequencies and sample rates. Compared to the Compact Disc, the much higher capacity DVD format enables the inclusion of either: -Considerably more music (with respect to total running time and quantity of songs) or -Far higher audio quality, reflected by higher linear sampling rates and higher bit-per- sample resolution, and/or -Additional channels for spatial sound reproduction. The fidelity of the upsampled audio will be limited by the source material quality, when the master recording is in digital format, and may not exceed the quality of existing CD releases of the same albums. DVD-Audio supports bit depths up to 24-bit and sample rates up to 192 kHz, while CD audio is 16-bit, 44.1 kHz. DVD-Audio discs may optionally employ a copy protection mechanism called Content Protection for Prerecorded Media (CPPM).

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