Digital Compact Cassette - Technology - Data Track

Data Track

On pre-recorded tapes, the information about album artist, album title and track titles and lengths was recorded in the data track continuously for the length of the entire tape. This made it possible for players to recognize immediately what the tape position was and how to get to any of the other tracks (including which side of the tape to turn to), as soon as a tape was inserted and playback was started, regardless of whether the tape was rewound before inserting or not.

On user tapes, a track marker was recorded at the beginning of every track, so that it was possible to skip and repeat tracks automatically. The markers would be automatically recorded when a silence was detected during an analog recording, or when a track marker was received in the S/PDIF signal of a digital input source (this track marker would automatically be generated by CD players). It was possible to remove these markers (to "merge tracks"), or add extra markers (to "split tracks") without re-recording the audio. Furthermore it was possible to add markers afterwards that would signal the end of the tape or the end of the tape side, so that during playback, the player would stop the mechanism or fast-forward to the end of the A-side or would switch from A-side to B-side immediately.

On later generations of recorders, it was possible to make a third tape type, called "super user tapes", by entering title information for each track. However, contrary to prerecorded tapes, the title information was stored only once, at the start of the track, right after the track marker, so unlike prerecorded tapes it wasn't possible to see what the name of the track was at any position within the track (the user would need to rewind to the beginning of the track), and there was no way to enter album information. Entering track information was a slow process (although easier with a remote control), only upper-case characters were supported and some commonly-used symbols such as the apostrophe were missing.

The three tape types (prerecorded, user and super-user) are compatible with all recorders and it's impossible (and unnecessary) to recognize the difference between a user tape and a super-user tape without playing it. There were some interesting minor compatibility problems with text on super-user tapes (which might indicate that Philips never had a clear internal standard for how text recording should work); for example:

• Stationary recorders that had simple fourteen-segment displays, all track information was converted to upper case. They could display symbols that were impossible to enter with their own track info editors (such as the apostrophe).
• The Philips DCC-822 car stereo had a full dot-matrix text display which could display upper case and lower case titles from prerecorded tapes as well as super-user tapes
• Portable recorders were able to display text from prerecorded tapes, but not from super-user tapes. Interestingly, this was impossible even on the DCC-175 which was capable of recording the text information (via the computer) unlike the other portables which didn't have the text recording capability at all.