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!