Support of audio numerical recording invented by Philips and Matsushita in 1992. It is presented outside under the same format as old the Minicassette. It was called commonly digital compact cassette or DCC . Name indicates also the apparatus able to read and record these cassettes.
History and technology
The digital compact cassette was launched with an aim of succeeding the standard analogical minicassette and of competing with the Minidisque (MANDELEVIUM) and DAT. Unfortunately she never managed to be essential near the general public.Cassette DCC, although having the same format that the minicassette, was rather appeared as a cartridge: a metal trap door protected the cores and bandages it and there was one direction to introduce it. it is the reader-recorder which took care of the car-reverse, the play-back head being swivelling.
It thus had the undeniable advantage to share the same format as the analogical cassettes, and the recorders of DCC could indifferently read one or the other type of cassette. This upward compatibility was to make it possible its users to adopt the numerical recording without making obsolete their collection of Minicassette S. The analogical cassettes could only be read, generally with the reductions of breath Dolby B or C if need be.
With the difference of the DAT or video tape recorder which uses a rotary head, recorder DCC used a multitrack fixed head. The recording was thus linear. To allow one recording density numerical sufficient, the writing was made on 9 parallel tracks, 8 data tracks and 1 timing track. This sparing system not very used 10 times more band than a cassette DAT, so that the capacity of a DCC was only 45 minutes uninterrupted (by face) whereas a cassette DAT makes it possible to reach 4 hours (with a definitely higher sound quality).
Moreover a coding of audio compression, called PASC (Precision Adaptive Sub-band Coding), (4:1 report/ratio similar to MPEG-1) was used to ensure one reasonable duration (without compression, cassette DCC would have allowed only 12 minutes of recording PCM by face). Although the PASC gave a better audio quality than coding ATRAC (used in the original MANDELEVIUM), it was not as good as the DAT, which uses noncompressed PCM.
The production of DCC was abandoned in November 1996 after Philips admitted that it had carried out very few sales.
Retrospectively it is clear that the magnetic bands with linear recording were already completely exceeded in 1992, not being as flexible and practical use as the diskette, and the arrival of the recordable compact disks (CD-R and CD-RW) returned the use of the obsolete traditional band for the needs for everyday consumption.
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