Columbia Records

==== Quadraphonic Sound ====
During 1971 Columbia began producing records in four-channel [[quadraphonic sound]], using the "[[Stereo Quadraphonic|SQ Quadraphonic]]" [[Matrix decoder|matrix decoding]] system. These recordings were backward compatible on conventional two-channel stereo playback systems, but played four-channels of [[surround sound]] when heard with special amplifiers and additional speakers. Artists using this technology covered all genres, including classical music [[Leonard Bernstein]] and [[Pierre Boulez]], plus popular artists such as [[Electric Light Orchestra]], [[Billy Joel]], [[Pink Floyd]], [[Johnny Cash]], [[Barbra Streisand]], [[Ray Conniff]], [[Santana (band)|Santana]], [[Herbie Hancock]], and [[Blue Öyster Cult]]. RCA had already begun releasing quadraphonic recordings on [[8-track tape]] starting in 1970, and countered on LP record with the [[Compatible Discrete 4|Quadradisc]] system. The RCA process required a special [[magnetic cartridge|phono cartridge]] for "discrete" four-channel playback unlike the Columbia "matrix" system. Although the Columbia process was simpler and quite effective, many consumers were confused by competing systems and sales of both were disappointing. Columbia released its last quadraphonic recordings in 1978. Starting in the 1990s multichannel surround sound music surged again with the popularity of [[home cinema]] systems. Many quadraphonic recordings were reissued in new surround sound formats such as [[Dolby Digital]], [[DTS (company)|DTS]], [[Super Audio CD]] and [[Blu-ray]], however, multichannel music still did not reach mass-market acceptance.