Leonard Feldman, "Quadcasting: A Progress Report on Four- channel FM," Stereo Review Nov. 73: 66-69. Leonard Feldman in 1974 was the technical director of the Institute of High Fidelity.
Japan Victor Corporation, CD-4: All you've Ever Wanted to Know about the CD-4 Disc System (n.p. 1974).
"CBS/Sony Announce Quadraphonic Disc Compatible SQ System," Hi-Fi Sound, 4 (Sept 1971): 72-3
"Four-Channel Records," Hi-Fi-Stereo Buyer's Guide Fall, 1972, p 46.
Bert Whyte, "Behind the Scenes," Audio May 1974, p 8 ; Julian D. Hirsch, "QS Drops the Gauntlet with its 'Vario- Matrix' System," Popular Electronics September 1973, p? [from a reprint];
Leonard Feldman, "Four Generations of Four-Channel Equipment," Stereo-Hi-fi Times 5 (Winter 1974): 47.
"Four-Channel: Dealers Feeling Software Pinch," Consumer Electronics March 1974, p 86, 88.
Art Weigold, "Four-Channel Compacts on Rough Ground," Consumer Electronics March 1974, 24-25.
Zenith Press Release, 30 May 1974.
"Juliette Stresses Compact 4-Channel 8-Track Record," Home Furnishing Daily 8 May 1974, p 10.
H. W. Hutchinson, "New 4-Channel at CES Tops Expectations," Home Furnishings Daily , 24 June 1974, p 5.
"Some Mfrs. Are Up, Others are Down on Quad," Home Furnishings Daily 14 May 1975, p. 5
Joe Brancatelli, "Quad Future Darkens as Mfrs. Cut lines," Home Furnishing Daily October 29, 1975
Edward Tatnall Canby, "Audio Etc." Audio August 1976, p ?
Fred Abatemarco, "Radio Shack Chain Dumping Its Private Label 4-Channel," Home Furnishings Daily 29 October 1975, p 20.
"FCC to Compare Matrix, Discrete 4-Channel Sound," Retailing Home Furnishings 9 August 1976, p. 54.
by David Morton
Multi-channel audio systems were used experimentally as early as the 1930s. Early proposals for stereo tape systems in the late 1940s included several three-channel types, but two-channel stereo was more easily implemented on long playing disks and 45-rpm records. Early pre-recorded stereo tapes also followed the two-channel model. But multi-channel experiments continued with the aim of enhancing the "realism" of recorded music.
An abortive quad system appeared in the 1950s for use in conjunction with FM broadcasting, but the FCC declined to approve it for commercial use.
Quadraphonic home systems began to look more economically feasible after transistors and integrated circuits began to be more widely used in consumer audio equipment in the 1960s, bringing costs down.
In 1970, JVC pushed forward with a new 4-channel technology, demonstrating its "CD-4" quadraphonic disk (not to be confused with the current Compact Disk).
Between 1970 and 1972, several other 4-channel systems appeared under various names and spellings, including Quadraphonic, Quadriphonic, Quadrophonic, Quadrisonic, Quadrasonic, and Tetrasonic. Just plain "Quad," though widely used to describe these devices, was actually trademarked in 1962 by an obscure British company (which in fact did not make 4-channel audio equipment!)
Besides the CD-4 system, the most popular quad formats were the Electro-Voice system (later called "RM" or Regular Matrix) the CBS "SQ" (Stereo-Quadraphonic) system and the Sansui "QS" system (apparently nearly indistinguishable from RM).
Record and electronics companies had to decide for themselves which system to adopt, with some such as Sony choosing SQ and others, such as RCA, choosing CD-4. By 1973, two more formats had been added, this time on tape. RCA in that year began to offer its first "Mark 8" quad 8- track systems, and several record companies offered discrete four-channel recordings on reel-to-reel tape.
Additionally, the matrixed systems could be broadcast over existing FM stations, and by late 1974 there were over 200 U.S stations experimentally using the Sansui system. The FCC launched a study to compare quad broadcasting standards, although it didn't announce its findings until late 1977.
As more and more companies became interested in quad, the catalog of available recordings expanded and the prices of equipment came down. By 1974, there were approximately 400 titles available on quad disks or 8- track tapes, and 75 on open-reel tapes. Equipment prices began to drop significantly after Motorola Corporation introduced a single-chip decoder suitable for several of the matrixed disk formats.
However, the electronics press claimed that record manufacturers, record retailers, and electronics dealers never fully supported these products. Record companies and retailers complained about the "dual inventory" problem related to carrying the same titles in multiple formats, particularly since they were already compelled to stock LP, 8-track, and, increasingly, cassette versions of popular releases. More enthusiastic were the quad record clubs that began to spring up to cater to four channel fans.
By 1975, A&M and EMI records had stopped issuing new releases in multiple formats, with the former choosing to stick with CD-4 and the latter SQ. That year, High Fidelity's editor complained that electronics dealers represented "the least enthusiastic group in the country where quad is concerned," reflecting the declining sales of equipment.
By the end of 1975 most large electronics chains began discounting quad equipment by up to 50 per cent in order to clear it out. Harman Kardon, Sherwood and other companies declared that they would stop quad production, and Radio Shack closed out its brand of quad equipment to make way for the next big fad, the Citizen's Band radio.
The fact that sales of quad reel-to-reel decks never quite fulfilled expectations was an unanticipated boon for musicians == the lines of high-end recorders designed by TEAC and other companies for quad fans were hastily repackaged as multi track "home studio" equipment, resulting in one of the first relatively affordable multi track recorders with separate inputs, preamplifiers, and level controls for four channels.
By August of 1977, quad had run its course. Apparently the only manufacturer to offer a new product that year was Sansui, which had two quad receiver models in its catalog.
Ironically, the FCC completed its tests of matrixed FM broadcasting and submitted its findings to the public for comment. In 1978, it issued standards for quad broadcasts, but by that time public interest had waned.
As late as 1979, the audiophile press was still hyping quad, with well-known audio journalist Len Feldman claiming that 4-channel broadcasting was still "very much alive." In fact, four-channel audio was not to be heard from again until the current fad for "surround sound" television.
David Morton (email@example.com)