The 4-track cartridge format had a head start over 8-tracks. Developed in 1956, the 4-track format was originally forsaken as unmarketable, and lay dormant until the early '60s (as far as the consumer market goes), when enterprising Earl Muntz saw its potential. He acquired rights to the format and began marketing both players and prerecorded tapes, licensing music from major record labels. The development of the 8-track format took the basic 4-track technology and refined it, making changes designed to make the tape less likely to jam while playing, and to increase accessibility to individual selections on the tape.
In the 4-track format, the pinch roller (the wheel that moves the tape along as it plays) was housed in the player. The 4-track cartridge had two programs--the tape played all the way around the loop, then switched to the second track and did the same thing all over again. In fact, the format took its name from the fact that two programs, each with two tracks of information (left and right channels of a stereo mix) equals four tracks. The two programs of the 4-track format were like the two sides of an LP, each holding roughly half the total program material.
Despite 4-track's potential to deliver better sound quality, it was the 8-track format that eventually dominated. Not the least reason for this was Ford's de facto endorsement. The physical similarity between 4- and 8-track cartridges permitted the development of converters that fit into the increasingly obsolete 4-track tapes and enabled them to be played in 8-track players. -- excerpted from "You Really Got Me," copyright © 1994 by Doug Hinman and Jason Brabazon (and corrected by Larry Blumenfeld)
More 4-track Stuff:
4-track Ads, Players, Tapes, Articles
Earl Muntz, the 4-Track Madman