
The Muntz Stereo-Pak, commonly known as the 4-
track cartridge, is a
magnetic tape sound recording cartridge technology.
The Stereo-Pak cartridge was inspired by the
Fidelipac 2-track monaural (audio & cue tracks, later 3-track for stereo) tape cartridge system invented by
George Eash in 1954 and used by radio broadcasters for commercials and jingles in 1959. The Stereo-Pak was adapted from the Fidelipac cartridge design by
Earl "Madman" Muntz in 1962, in partnership with Eash, as a way to play pre-recorded tapes in cars.
[Jay Ehler]
Earl Muntz Meets George Eash
Billboard vol. 84, No. 47, 18 November 1972, p. 62, 76, 78
The tape is arranged in an infinite loop that traverses a central hub and crosses a tape head, usually under a pressure pad to assure proper tape contact. The tape is pulled by tension, and spooling is aided by a lubricant, usually
graphite
Graphite () is a Crystallinity, crystalline allotrope (form) of the element carbon. It consists of many stacked Layered materials, layers of graphene, typically in excess of hundreds of layers. Graphite occurs naturally and is the most stable ...
.
History
The
endless loop tape cartridge was designed in 1952 by
Bernard Cousino of
Toledo, Ohio
Toledo ( ) is a city in Lucas County, Ohio, United States, and its county seat. It is located at the western end of Lake Erie along the Maumee River. Toledo is the List of cities in Ohio, fourth-most populous city in Ohio and List of United Sta ...
.
Previously, music in the car had been restricted mostly to radios. Records, due to their methods of operation and size, were not practical for use in a car, although several companies tried to market automobile record players such as the
Highway Hi-Fi and the Auto-Com flexidisc.
Entrepreneur
Earl "Madman" Muntz of Los Angeles, California, saw a potential in Fidelipac broadcast carts for an automobile music tape system, and in 1962 introduced his "Stereo-Pak 4-Track Stereo Tape Cartridge System" and pre-recorded tapes, initially in California and Florida. He licensed popular music albums from the major record companies and duplicated them on these 4-track cartridges, or CARtridges, as they were first advertised.
Music came in four cartridge sizes.
* AA (single) size was an inch wide by two inches long and carried the same amount of time per track (6 minutes) as one side of a
45 RPM EP.
* A-size, 4 inches wide by 5 inches long, was the most common size. The same size as the vast majority of NAB (Fidelipac) carts, it was able to carry a 3-inch reel.
* B-size, six inches wide by 7 inches long, was used infrequently for
2-LP sets and other extended programs. Able to carry a 5-inch reel.
* C-size, able to carry a full 1800-foot 7-inch reel of one-mil tape, used infrequently for extremely extended 4-LP sets.
Muntz developed and marketed a variety of mobile and stationary players and recorders for his 4-track tapes.
["Muntz"](_blank)
"Tape Recorder Directory," '' HiFi'' / '' Stereo Review's'' ''Tape Recorder Annual 1968'', page 96, retrieved May 22, 2023. (Details on various Muntz 4-track players and recorders, with photos)
The B- and C-size carts would have their stereo sound split to mono and be used for background music systems all the way up to the early 1990s, when digital took over. In the last part of that period, a last-ditch effort to reduce cost came in the form of reducing the tape speed first to 1-7/8
IPS and then to 15/16 IPS, while reducing the cartridge size first back to the standard widely available A-size and then to a hybrid size between the AA (single) size and the A-size. At first, chromium high-bias tape was used to offset the loss of fidelity from the lower speed, and then, when that proved too expensive, cobalt-based tape was substituted.
After riding in Muntz's car and listening to his 4-track cartridge system, electronics and aerospace entrepreneur
Bill Lear had an employee of
Lear Jet Corporation create a modified derivative, resulting in the more convenient and long-playing
8-track cartridge system, which quickly supplanted and surpassed the 4-track in the market until being surpassed, itself, by the
cassette tape
The Compact Cassette, also commonly called a cassette tape, audio cassette, or simply tape or cassette, is an analog audio, analog magnetic tape recording format for Sound recording and reproduction, audio recording and playback. Invented by L ...
system.
See also
*
PlayTape
PlayTape is a audiotape format and mono or stereo playback system introduced in 1966 by Frank Stanton (entrepreneur), Frank Stanton. It is a two-track system, and was launched to compete with existing 4-track cartridge technology. The tape cart ...
*
HiPac
*
8-track cartridge
*
Album era
The album era (sometimes, album-rock era) was a period in popular music, usually defined as the mid-1960s through the mid-2000s, in which the album—a collection of songs issued on physical media—was the dominant form of recorded music expr ...
*
Timeline of audio formats
An audio format is a medium for sound recording and reproduction. The term is applied to both the physical recording media and the recording formats of the audio frequency, audio content—in computer science it is often limited to the audio file ...
*
Sound recording and reproduction
Sound recording and reproduction is the electrical, Mechanical system, mechanical, electronic, or digital inscription and re-creation of sound waves, such as spoken voice, singing, instrumental music, or sound effects. The two main classes of ...
*
Birotron
References
{{Audio format
Audiovisual introductions in 1962
Audio storage
History of sound recording
Tape recording
Discontinued media formats
American inventions
1962 in music
1962 in technology
Products introduced in 1962