Stereo 8, commonly known as the eight-track cartridge, eight-track tape, or simply eight-track, is a magnetic tape sound recording technology. It was popular in the United States from the mid-1960s through the late 1970s. Stereo 8 was created in 1964 by Bill Lear of Lear Jet Corporation, along with Ampex, Ford Motor Company, General Motors, Motorola, and RCA Victor Records (RCA). It was a further development of the similar Stereo-Pak four-track cartridge created by Earl “Madman” Muntz. A later quadraphonic version of the format was announced by RCA in April 1970 and first known asQuad-8, then later changed to just Q8.
The popularity of both four-track and eight-track cartridges grew from the booming automobile industry. In September 1965, Ford Motor Company introduced factory-installed and dealer-installed eight-track tape players as an option on three of its 1966 models (Mustang, Thunderbird and Lincoln), and RCA Victor introduced 175 Stereo-8 Cartridges from its RCA Victor & RCA Camden artist’s catalogs.
By the 1967 model year, all of Ford’s vehicles offered this tape player upgrade option. Thanks to Ford’s backing, the eight-track format quickly won out over the four-track format, with Muntz abandoning it completely by late 1970.
Despite its problems, the format gained steady popularity because of its convenience and portability. Home players were introduced in 1966 that allowed consumers to share tapes between their homes and portable systems. “Boombox” type players were also popular. With the availability of cartridge systems for the home, consumers started thinking of eight-tracks as a viable alternative to vinyl records, not only as a convenience for the car. Within a year, prerecorded releases on eight-track began to arrive within a month of the vinyl release. Eight-track recorders had gained popularity by the early 1970s.
Quadraphonic eight-track cartridges (announced by RCA in April 1970) were also produced, with the major auto manufacturers being particularly eager to promote in-car quadraphonic players as a pricey option. The format enjoyed a moderate amount of success for a time but faded in the mid-1970s. These cartridges are prized by collectors since they provide four channels of discrete sound, unlike matrixed formats such as SQ. Most quadraphonic albums were specially mixed for the quad format.
There are numerous reasons for the format’s decline. While the cassette offered features that the eight-track lacked, such as smaller size and rewinding capability, it also had disadvantages: 1) Its tape speed was half that of Stereo 8, producing theoretically lower sound quality, and 2) It required greater mechanical complexity of the player. However, constant development of the cassette turned it into a widespread high-fidelity medium and also lowered the cost and complexity. That, combined with the inherent deficiencies of the Stereo 8 format contributed to its decline.
In the U.S., eight-track cartridges were phased out of retail stores by late 1982.