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Digital Compact Cassette

Media type:	Magnetic tape
Encoding:	Precision Adaptive Sub-band Coding
Capacity:	105 minutes
Write mechanism:	multi-track stationary head
Developed by:	Philips & Matsushita
Usage:	audio
Extended from:	Compact cassette

Digital Compact Cassette (DCC) was a short-lived sound recording format introduced by Philips and Matsushita in late 1992. Pitched as a successor to the standard analog cassette, and competitor to MiniDisc (MD) and Digital Audio Tape (DAT), it never became popular with the general public. It shared the same form factor as analog 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.

A DCC is a multi-track stationary head recorder, unlike a rotary-head or helical scan recorder such as DAT or VHS, whose heads are moving relative to the tape. In order to achieve the required bit rate for audio, nine heads are used for writing eight parallel data tracks plus one timing track. The track width, determined by the distance between neighbouring heads is larger, about a factor of ten, than that of a typical rotary-head recorder. As a result the capacity of a DCC is only 105 minutes, compared to 3 hours for DAT. An audio compression codec, called PASC (Precision Adaptive Sub-band Coding), 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 it was not as good as DAT, which used uncompressed PCM.

DCC was discontinued in November 1996 after Philips admitted it had achieved 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 compact discs (CD-RWs) 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.

A derivative technology developed for DCC is now being used for filtering beer. Silicon wafers with micrometer scale holes are ideal for seperating yeast particles from beer. The beer flows through the silicon wafer leaving the yeast particles behind, which results in a very clear beer. The manufacturing process for the filters was originally developed for the read/write heads of DCC players.^[1]

• DAT
• DVD
• Universal Media Disc (UMD)

1. ^ Hi-fi failure helps to brighten beer - New Scientist Retrieved 2007-4-2.

• DCC
• DCC900