8-track cartridge

The 8-track tape (formally Stereo 8; commonly called eight-track cartridge, eight-track tape, and eight-track) is a magnetic-tape sound-recording technology that was popular from the mid-1960s until the early 1980s, when the compact cassette, which antedated the 8-track system, surpassed it in popularity for recorded music.

The format was commonly used in cars and was most popular in the United States and Canada, and to a lesser extent, in the United Kingdom, Ireland, and Japan. One advantage of the 8-track tape cartridge was that it could play continuously in an endless loop, and did not have to be ejected, turned around, and reinserted to play the entire tape. After about 80 minutes of playing time, the tape would start again at the beginning. Because of the loop, no rewind is needed. The only options the user has are play, fast forward, record, and program (track) change.

The Stereo 8 Cartridge was created in 1964 by a consortium led by Bill Lear of Lear Jet Corporation, along with Ampex, Ford Motor Company, General Motors, Motorola, and RCA Victor Records (RCA—Radio Corporation of America).

The 8-track tape format is now considered obsolete, although some collectors refurbish these tapes and players, and some bands issue these tapes as a novelty. Cheap Trick's The Latest in 2009 was issued on 8-track, as was Dolly Parton's A Holly Dolly Christmas in 2020, the latter with an exclusive bonus track.

The cartridge's dimensions are roughly 5.25 by 4.0 by 0.8 inches (13.3 cm × 10.2 cm × 2.0 cm). The magnetic tape is played at 3.75 inches per second (twice the speed of a cassette), is wound around a single spool, is about 0.25 inches (0.64 cm) wide and contains eight parallel tracks. The player's head reads two of these tracks at a time, for stereo sound. After completing a program, the head mechanically switches to another set of two tracks, creating a characteristic clicking noise.

Inventor George Eash came up a design in 1953, called the Fidelipac cartridge, or the NAB cartridge, which would later be used in not only the Muntz Stereo-Pak, but also in various monaural background music systems from the late 1960s to the early 1990s.

His inspiration came from one of the first products that used the endless tape cartridge technology, which was the Audio Vendor from a year earlier, an invention of Bernard Cousino. The tape is passed through an inner ring of loose tape reel, where the recording is stored, and looped back through the outer ring of the reel. Initially, this mechanism was to be implemented in a reel-to-reel audio tape recorder.

Later, Cousino developed a plastic case that could be mounted on some existing tape recorders. This cartridge was marketed by John Herbert Orr as Orrtronic Tapette. In this generation, the tape was wound with the magnetic coating facing the inside of the reel. Later cartridge types had the magnetic layer facing the outside of the reel, so it had to be played by a specially designed recorder. Once traction of the tape by capstan was added, users had the convenience of just pushing the cartridge into the recorder without having to thread the tape. These cassettes needed no internal space for the tape head slider because they accessed the tape from outside the cartridge.