System UHJ: a hierarchy of surround sound transmission systems

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.