Phase 4 Stereo
Phase 4 Stereo was a branch of Decca and its American label London Records created in 1961.[1] Phase 4 Stereo supposedly created better sound by being recorded on a 10-channel, and later 20-channel, recording console.[2] Approximately two hundred albums were released under the label, including popular music, "gimmick" records engineered to make the sound travel from speaker to speaker, records featuring percussion effects, and historical sound effect records. In 1964, a light classical Phase 4 "Concert series" was produced.
The concept of Phase 4 Stereo has nothing to do with four channel stereo. But because there often are sounds out of phase the records give good results when played on Hafler circuits or other simulated four channel systems.
In 1996 a CD, The Phase 4 Experience, was released with recordings from 1966 to 1979 (London 444 788-2 LPX/PY 871).