| Media type | magnetic tape |
|---|---|
| Encoding | analog signal |
| Capacity | Four stereo channels |
| Read mechanism | tape head |
| Write mechanism | magnetic recording head |
| Usage | audio storage |
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, but was relatively unknown in many European countries. Stereo 8 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). 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 as Quad-8, then later changed to just Q8.
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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 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, 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 was very successful.
The endless loop tape cartridge was first designed in 1952 by Bernard Cousino around a single reel carrying a continuous loop of standard 1/4-inch, plastic, oxide-coated recording tape running at 3.75 in.(9.5 cm) per second. Program starts and stops were signaled by a one-inch-long metal foil that activates the track-change sensor. (Bill Lear had tried to create an endless-loop wire recorder in the 1940s, but gave up in 1946, even though endless-loop 8 mm film cartridges were already in use for him to copy from. He would be inspired by Earl Muntz's four-track design in the early 1960s.)
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 Broadcasters 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 four-track cartridge 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 four-track cartridges, or "CARtridges", as they were first advertised.
The Lear Jet Stereo 8 track cartridge was designed by Richard Kraus while working under Bill Lear and for his Lear Jet Corporation in 1963. The major change was to incorporate a neoprene rubber and nylon pinch roller into the cartridge itself, rather than to make the pinch roller a part of the tape player, reducing mechanical complexity. Lear also eliminated some of the internal parts of the Eash cartridge, such as the tape-tensioning mechanism and an interlock that prevented tape spillage. In the Cousino, Eash, Muntz, and Lear cartridges, tape was pulled from the center of the reel, passed across the opening at one end of the cartridge and wound back onto the outside of the same reel. The spool itself was freewheeling and the tape was driven only by tension from the capstan and pinch roller.
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, usually graphite and patented by Bernard Cousino, to ease the continuous slip between the tape layers. While the design allowed simple, cheap, and mobile players, unlike a two-reel system, it did not 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 (long playing) 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 comprising 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 from the narrower tape tracks. Unlike the Stereo-Pak, the Stereo 8 could switch between tracks automatically, with 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 into two parts (the split was often made during an instrumental break or a repeated chorus), song orders being reshuffled, shorter songs being repeated, and songs separated by long passages of silence. Some eight-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 eight-track was able to be arranged exactly like the record album version, without any song breaks. Examples of this are Quadrophenia by The Who, and some versions of Days of Future Passed by The Moody Blues. Other examples of this rarity are Freeways by Bachman-Turner Overdrive, Live Bullet by Bob Seger and the Silver Bullet Band, Caught Live + 5 by The Moody Blues, The Concert in Central Park by Simon & Garfunkel, and Octave by The Moody Blues.
In 1964, Lear's aircraft company constructed 100 demonstration Stereo 8 players for distribution to executives at RCA and the auto companies.
The popularity of both four-track and eight-track cartridges grew from the booming automobile industry.[1] 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.[2] 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.
Some of the inherent deficiencies of the format were: 1) high wow and flutter due to the constantly changing load presented by the sliding tape pack, 2) tendency to jam as the tape got dirty, the lubricant wore away, and the tape was exposed to heat, 3) flattening of the pinch roller, over time, when a cartridge was left plugged in, causing increased wow and flutter, 4) inability to attain and maintain head alignment due to the movable head design. As time went on, these issues were compounded as later cartridges started using cheaper, lower quality materials, such as plastic pinch rollers. Another contributing factor was an effort by record companies to reduce the number of formats offered. In the late 1970s, when sales of eight-tracks slipped, they were quick to abandon the format.
The professional broadcast cart format survived for more than another decade at most radio stations. It was used to play and switch jingles, advertisements, station identifications, and music content until it was replaced by various computer-based methods in the 1990s. This format survived longer because it was used for relatively short sound loops, where starting from the beginning was more important than other criteria. The endless loop tape concept continues to be used in modern movie projectors, although in that application the spool is actively rotated and not drawn by tension on the film. That too, however, is being supplanted by digital cinema technologies.
Eight-track players became less common in homes and vehicles in the late 1970s. By the time the compact disc arrived in 1982–1983, the eight-track cartridges had greatly diminished in popularity. In some Latin American countries as well as European, the format was abandoned in the mid-70s in favor of the cassette.
It was a popular and highly portable music format, suitable for use in the home, recreation, and vehicles. It reached a wide market and perpetuated the recordings of a majority of music genres. The eight-track format maintains a cult following with avid collectors even after its demise on the open market.
In the U.S., eight-track cartridges were phased out of retail stores by late 1982. Some titles were still available as eight-track tapes through Columbia House and RCA (BMG) Music Service Record Clubs until late 1988. Many of these late-period releases are highly collectible because of the low numbers that were produced and the few customers who ever purchased them. Among the most rare is Stevie Ray Vaughan's Texas Flood. Another is Bruce Springsteen and the E Street Band's Live/1975-85, which was one of the very few boxed sets to be released on vinyl, cassette, compact disc, and eight-track tape.
There is a debate among collectors about the last commercial eight-track released by a major label, but many agree it was Fleetwood Mac's Greatest Hits in November 1988.[3] The last eight-track tapes by major recording companies were from record and tape clubs in 1988 like RCA (BMG Music) and Columbia House (CRC). All of the known final pre-recorded 8-tracks released commercially are documented at the "Reel To Reel / 8 Track Index" Website with complete list and scanned photos of all products. Demographics had country and western 8-tracks selling possibly the strongest at that time. Readers Digest also had exclusive releases at least as late as 1989 aimed at fans of older classic recording and easy listening and country. Rock and pop 8-tracks from the late 1980's are quite rare and in high demand and can sell on ebay as high as $200.00 each depending on the popularity of the music group.
There are reports of bootleg eight-track tapes being made in Mexico as late as 1995.[4] Some independent artists still release eight-track tapes.[5] Also, bands sometimes release eight-tracks as special releases; for example, The Melvins released a limited-time, live eight-track album[6] and Cheap Trick issued a limited edition version of their album The Latest on the format on June 23, 2009.[7] In the book Journals, Kurt Cobain wrote about wanting to release Nirvana's last studio album, In Utero, as an 8-track tape, but this never happened. Apart from a selected group of highly collectible artists, the record club issues, and the quadraphonic releases, many eight-track tapes seem to have limited value to most collectors, especially if the tapes have been misused or appear to be worn.
The cartridges have an audible pause due to the presence of a length of metallic foil, which a sensor detects and signals the end of the tape and acts as a splice for the loop. The foil passes across a pair of electrical contacts which are in the tape path. Contact of the foil closes an electrical circuit that engages a solenoid which mechanically shifts the tape head to the level of the next track.
Most players produced a mechanical click when switching programs, although early Lear players switched silently. Because of the expense of producing tape heads capable of reading eight tracks, most eight-track players have heads that read just two tracks. Switching from program to program is accomplished by moving the head itself. Since the alignment of the head to the tape is crucial to any tape system, and because eight-track systems were generally designed to be cheap, this configuration further degraded the sound of the eight-track tape.
The Stereo 8 system was fairly simple, mechanically, but presented difficulties in two primary areas:
1) Capstan wear and buildup. As tape residue, dirt and lubricant built up on the capstan, the tape speed would increase and, since the buildup was uneven, the tape speed would become correspondingly uneven. Similarly, some units were subject to the capstan wear, causing a decrease in tape speed.
2) Head alignment. This was an issue for two reasons: a) Azimuth misalignment results in reduced high frequencies, and b) Head height misalignment allows sounds from adjacent tracks to bleed over, an effect sometimes known as "double-tracking". This format, unlike other tape formats, features a movable head with four positions. Among audio service technicians, there used to be a joke that "the eight-track is the only audio device which knocks itself out of alignment four times during each album."
Another issue with azimuth misalignment is a loss of stereophonic-image accuracy. This is due to the resultant time delay between the left and right channels resulting in a degradation of phase correlation. This effect is enhanced in an 8-track system, as compared to either reel-to-reel or cassette, due to the larger physical distance, on the tape, between the left and right channel tracks. This effect could often be cured (or induced) by insertion of a match book in the player opening alongside the cartridge, shifting the alignment slightly.
Stereo 8 tapes and players developed a reputation for unreliability, mostly because of the phenomenon of having the player "eat" the tape as well as occasional failures of splicing tape. The automobile environment, with its temperature extremes, vibration, dust and so on, contributed to many failures.
The "melted" rubber pinch rollers that can be found in many early 8-Track cartridges were the result of the rubber not being fully cured. After discovering this cause, later cartridges used only fully cured (hard) rubber pinch rollers that did not deteriorate, as much, over time.
Tape tension was another cause of unreliability. Prerecorded eight-track tapes tended to hold only a single album, about 46 minutes of content, or 11.5 minutes per track. 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 (loop length). Over time, this would cause the tape pack to tighten, making it more difficult to feed, and to maintain a constant playback speed.
When the sliding tape pack would pull itself tight, for whatever reason, a jammed 8-track cartridge was the result. A quick solution was to hold the cartridge in one hand, facing down, while pulling out a section of, about 4-6' in length from the outer winding side. A quick tug on the tape would cause it to immediately wind in and the result was a loosened up tape pack that would play correctly.
Failing that, another solution was to open the cartridge, cut the tape at the splice, and relieve the excess tension by manually unwinding one or two sections from the outer edge of tape (loop length) while keeping the reel stationary, then re-splicing the tape, 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). Another, simpler fix was to shake the cassette in the plane of the tape reel with a rotary motion, sometimes this would cause the windings inside to rotate and loosen.
A decrease in the quality of the parts used in the eight-track cartridge, that is, plastic pinch rollers, lubricant quality and quantity, etc., was another blow to the faltering format. As problems further reduced the reliability, the sound quality, and the smoothness of the tape speed. As a result, the eight-track eventually developed a reputation for being finicky and unreliable.