Abstract :
The reproduction of sounds from all directions in the horizontal plane, commonly known as surround sound, offers new scope for greater realism of the reproduced sound and a new dimension for creative and dramatic effects. Although a large number of loudspeakers are almost certainly needed to reproduce surround sound convincingly, a worthwhile improvement may be given with just four loudspeakers in a rectangular array, i.e. quadraphony. This paper describes a hierarchical transmission system for quadraphony, System UHJ. Transmission may be by 2¿, 2¿¿, 3¿ or 4¿channels, the high-order channels being added to the base channels, thereby forming a hierarchy of systems. The design and development of the 4¿2¿4 System HJ is discussed in some detail although this paper necessarily only gives a brief account of the many facets of this involved subject.
