Digital Compact Cassette
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Digital Compact Cassette (DCC) was a short-lived audio format created by Philips in the early 1990s. Pitched as a competitor to Minidisc (MD), it never caught on with the general public. It shared its form factor with standard analogue cassettes, and players were designed to accept either type of tape. The idea was to provide this backward compatibility so users could adopt digital recording without having to make their tape collections obsolete. In practice it has been shown that consumers are often ready to adopt new technology without such backward compatibility.
A DCC is a multi-track stationary-head recorder. Unlike a rotary-head or helical scan recorder, such as audio DAT or video VCR, where the heads are moving relative to the tape, the heads are fixed (and thus only the tape is moving). In order to achieve the required bit rate for audio, multiple heads for reading and writing are used in parallel. The track width, determined by the distance between neighbouring heads is much larger, about a factor of ten, than that of a typical state-of-the-art rotary-head recorder. As a result the information capacity of a DCC is much less than that of a DAT, and an audio compression codec, called PASC, which is a 4:1 scheme similar to MPEG-1, was used to supply sufficient playing time. Many believed this gave better quality audio than ATRAC (used in the original MD), but not as good as DAT, which used uncoded PCM.
DCC was discontinued in 1996 after Philips admitted it had achieved only poor sales. In hindsight it is clear that linear tape formats are not as versatile or robust as disc type formats, and the advent of recordable CD discs makes the use of tape obsolete for consumer applications. Professional recording studios still use DAT machines for their higher sample rate (48 kHz), and frequently for their portability. ADAT machines are also still in widespread use in the recording industry.
Links
- DCC (http://www.xs4all.nl/~jacg/philips/dcc.html)ja:デジタルコンパクトカセット