GB1427206A - Recording quadraphonic sound - Google Patents

Abstract

1427206 Quadraphonic matrix encoders CBS Inc 11 Sept 1973 [13 Sept 1972] 42697/73 Heading H4R In a quadraphonic matrix encoder channel signals L T and R T are provided which each carry a respective signal L f and R f together with equal proportions of both L b and R b signals which are phase shifted so that like signals in the two channels are in quadrature with the Lb signal in one channel leading the L b signal in the other and the R b signal in the one channel lagging the Rb signal in the other. In one embodiment Fig. 2, the matrix applies the same phase shift to the L f and R f signals as is given to the L b and R b signals respectively, Fig. 2A, while in a second embodiment, Fig. 3, the matrix is switchable to provide, in the position shown, the same matrix configuration as is described in Specification 1,387,874, providing output signals as shown in full line in Fig. 3A, or with switch 142 in its other condition a frequency dependent phase shift of both L f and R f relative the phase shift applied to L b and R f , shown by the dotted vectors in Fig. 3A. With switch 120 in the opposite position to that shown the channel signals have relative phase positions as shown in Fig. 3B. The arrangements provide better location of some sound images under particular conditions of use with particular original sound locations.