MATRICES PERFECTIONNEES DE CODAGE ET DE DECODAGE POUR ENREGISTREMENTS QUADRIPHONIQUES

摘要

Method and apparatus for recording four separate channels of information on a medium having only two independent tracks, such as a phonograph record, and method and apparatus for reproducing such information and presenting it on four loudspeakers to give the illusion of sound coming from four separate sources. The signals recorded in the manner described in this application are also reproducible on conventional stereophonic playback systems, distributing the four separate channels to the two loudspeakers in a manner to give a balanced and symmetrical reproduction. Two embodiments of encoding apparatus for combining the four input signals preparatory to recording on the two-track medium, and two decoders, one for each of the encoding systems, are described.