Eight track audio cartridges or 8-Track Tapes were popular in the United States from the mid 1960s to the early 1980s. Strangely, they didn't much use elsewhere in the world.
The DA-88 was a digital multitrack recording device introduced by the TASCAM division of the TEAC Corporation in 1993. This modular, digital multitrack device uses tape as the recording medium and could record up to eight tracks simultaneously. It also allowed multiple DA-88 devices to be combined to record 16 or more tracks. Audio data was stored in the DTRS (Digital Tape Recording System) format on Hi-8mm video compact cassettes, allowing up to 108 minutes of continuous recording on a single tape.
In the 90's many musicians used Fostex and other brands of analog 4 track recorders to create multi-track recordings of their songs. Most of these recorders used standard compact cassettes tapes. Cassettes used in these devices cannot be played back on regular cassette players because the 4 track recorder used both sides of the cassette at the same time. 4 track recorders also ran at a higher speed for better quality. Bring us your 4 track cassettes and we will digitize them!