Stereo 8, commonly known as the 8-track cartridge, 8-track tape, or 8-track, is a magnetic tape sound recording technology, popular from the mid-1960s to the early 1980s. Stereo 8 was created in 1964 by a consortium led by Bill Lear of Lear Jet Corporation, along with Ampex, Ford, Motorola and RCA Victor Records. It was a further development of the similar Stereo-Pak 4-track cartridge created by Earl "Madman" Muntz. A later quadraphonic version of the format was known as Quad 8 or Q8.
The original format for magnetic tape sound reproduction was reel-to-reel audio tape recording, first made widely available in the late 1940s. However, threading tape into the recorders was more difficult than simply putting a disc record onto a phonograph player. Manufacturers introduced a succession of cartridges which held the tape inside a metal or plastic housing to eliminate handling. The first was RCA Victor, which in 1958 introduced a cartridge system called Sound Tape or Magazine Cartridge Loading, but until the introduction of the Compact Cassette in 1963 and Stereo 8 in 1965, none were very successful.
The endless loop tape cartridge was first designed in 1952 by Bernard Cousino of Toledo, Ohio, around a single reel carrying a continuous loop of standard 1/4-inch, plastic, oxide-coated recording tape running at 3.75 inches per second (9.5 centimeters per second). Program starts and stops were signaled by a metal foil 1 inch long that activates the track change sensor.
Inventor George Eash, also from Toledo, invented a cartridge design in 1954, called the Fidelipac. The Eash cartridge was later licensed by manufacturers, notably the Collins Radio Corporation, which first introduced a cartridge system for broadcasting at the National Association of Broadcaster's 1959 annual show. Fidelipac cartridges (nicknamed "carts" by DJs and radio engineers) were used by many radio stations for commercials, jingles and other short items right up until the late 1990s when digital media took over. Eash later formed Fidelipac Corporation to manufacture and market tapes and recorders, as did several others including Audio-Pak (Audio Devices Corp.).
There were several attempts to sell music systems for cars, beginning with the Chrysler "Hiway hi-fi" of the late 1950s (which used discs). Entrepreneur Earl "Madman" Muntz of Los Angeles, California, however, saw a potential in these "broadcast carts" for an automobile music system. In 1962 he introduced his Stereo-Pak 4-track stereo system (two programs, each consisting of two tracks) and tapes, mostly 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. Stereo-Pak tape cartridges were commercially available from a number of companies, notably Fidelipac.
With a reel turning at a constant rate, the tape around the hub has a lower linear velocity than the tape at the outside of the reel, so the tape layers must slip past each other as they approach the center. The tape was coated with a slippery backing material patented by Bernard Cousino, usually graphite, to ease the continuous slip between the tape layers. While the design allowed simple, cheap, and mobile players, unlike a two-reel system it didn't permit rewinding of the tape. Some players offered fast-forward by speeding up the motor while cutting off the audio, but rewinding was never offered, because it was technically impossible.
Muntz's cartridge had used two pairs of stereo tracks in the same configuration as then-current "quarter track" reel to reel tapes. This format was intended to parallel his source material, which was usually a single LP record with two sides. Program switching was achieved by physically moving the head up and down mechanically by a lever. The Stereo 8 version doubled the amount of programming on the tape by providing eight total tracks, usually consisting of four programs of two tracks each. Lear touted this as a great improvement, because much more music could be held inside a standard cartridge housing, but in practice this resulted in a slight loss of sound quality and an increase in background noise due to the narrower tape tracks. Unlike the Stereo-Pak, the Stereo 8 could switch between tracks automatically, due to the use of a small length of conductive foil at the splice joint on the tape, which would cause the player to change tracks as it passed the head assembly.
The Stereo 8 also introduced the problem of dividing up the programming intended for a two-sided LP record into four programs. Often this resulted in songs being split in two parts, reshuffled song orders, shorter songs being repeated, or long passages of silence. Some 8-tracks included extra musical content to fill in time such as a piano solo on Lou Reed's Berlin and a guitar solo in Pink Floyd's "Animals" .
In rare instances, an 8-track would be arranged exactly like the record album version, with no song breaks. Examples of this are "Quadrophenia" by The Who, and some versions of "Days of Future Passed" by The Moody Blues.
Lear's aircraft company constructed 100 Demo Stereo 8 players for distribution to executives at the auto companies and RCA in 1964.
Despite its problems, the format gained steady popularity due to its convenience and portability. Home players were introduced in 1966 that allowed consumers to share tapes between their home and portable systems. "Boombox" type players were also popular. With the availability of cartridge systems for the home, consumers started thinking of 8-tracks as a viable alternative to vinyl records, not only as a convenience for the car. Within a year, prerecorded releases on 8-track began to arrive within a month of the vinyl release. 8-track recorders had gained popularity by the early 1970s.
Quadraphonic 8-track cartridges (introduced by RCA Records in September 1970 and first known as Quad 8, and later just Q8) 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.
8-track players became less common in homes and automobiles in the late 1970s. By the time the Compact Disc arrived in 1982–83, the 8-track had greatly diminished in popularity.
It was a popular and highly portable music format suitable for home, recreation or vehicle that reached a wide market and perpetuated the recordings of a majority of music genres. The 8-track format maintained a cult following with avid collectors even after its demise on the open market.
There is a debate among collectors about what was the last commercially released 8 track by a major label, but many agree it was Fleetwood Mac's Greatest Hits in November 1988. The last 8-track tapes by major recording companies were from record and tape clubs in 1988 like RCA (BMG Music) and Columbia House (CRC). There are reports of bootleg 8-track tapes being made in Mexico as late as 1995 Some independent artists still release 8-track tapes Also, bands sometimes release 8-track as a special release, for example, the Melvins, who released a limited time 8 track live album Apart from a select group of highly collectible artists, the record club issues, and the quadraphonic releases, many 8-track tapes seem to have limited value to most collectors, especially if they have been misused or appear to be worn.
If the azimuth of the head became misadjusted, there would be a faint audio bleed of adjacent tracks into the currently playing track, known as "double-tracking", and a loss of stereophonic image accuracy, since a slight delay between channel (resulting from relative channel displacement, on the head's side, along the tape's direction) virtually ruins phase correlation, and, finally, a loss of frequency response, as with any misadjusted tape system.
Stereo 8 tapes and players developed a reputation for unreliability, due mostly to splice failures and the phenomenon of the player "eating" the tape. The auto environment, with its temperature extremes, vibration, dust, etc., caused many failures as well.
Tape tension was another cause of unreliability. Prerecorded 8-track tapes tended to hold only a single album, about 30 minutes of content. Consumers wanted the ability to record more music on a single cartridge, so manufacturers came out with units of greater capacity. With the corresponding increase in tape length, there was a greater velocity differential between the tape being drawn from the center of the reel and the tape being fed back to the outer edge of the reel as it passed the capstan/pinch roller assembly. Over time, this would cause the tape pack to tighten, making it more difficult to feed, and to maintain a constant playback speed.
One solution was to open up the cartridge, cut the tape at the splice, and relieve the excess tension by manually rotating the outer edge of the tape while keeping the reel stationary. The tape would then be re-spliced, with a fresh piece of foil, since the old foil was usually caked with built-up graphite, reducing conductivity and making it difficult to change tracks. This was a temporary fix at best, since by the time the problem manifested itself either by 'stuttering' during playback or physical noises coming from the cartridge during use, the tape and other internal components had already experienced significant damage.
A decrease in the quality of the parts used in the 8-track cartridge was a critical blow to the faltering format, as problems developed with the reliability, sound and smooth playing of the tape. Due to these problems, the 8-track developed a notorious reputation for being "finicky" and somewhat unreliable; however, it can be argued that most of the problems that plagued the format could have been entirely avoided if the manufacturers had only developed quality control standards for both the cartridges and players.
Old tapes may break at the channel-switching foil splice when the glues used during manufacture harden with age. Repair sometimes requires careful disassembly of the cartridge and the addition of a new metallic foil splice.
On some cartridges, a plastic and foam pressure pad behind the tape path holds the tape against the tape head as the tape moves across it. This material can disintegrate with age, leaving a glob of sticky material that will not support the tape against the head, and may damage the tape. A new foam pressure pad will remedy this problem, although this also requires cartridge disassembly.
Also, in many early cartridges 1965-1970, the rubber in the pinch roller, which pulls the tape across the heads, was not fully cured, and this caused them to deteriorate over time, melting into a sticky, tar-like material. These can be replaced with a new rubber pinch roller of the same size and proportions. Rubber pinch rollers manufactured after 1970 are made of fully cured rubber, which does not deteriorate over time. In late 1970, RCA Records even switched to a new plastic pinch roller, which some other companies also used. However, rubber is the preferred material for pinch rollers as it grips the tape better for more even and precise movement.