Single box surround sound

In this tutorial paper, the author introduces a full physical surround-sound system in a single equipment box, focusing on its background, novel technology, and its application. Working on the principles of phased-array antennas commonly used for electromagnetic waves, but adapted for the wide-bandwidth requirements of audio acoustics, Digital Delay Arrays (DDA) simultaneously produce multiple independently-steered and -focused beams of sound each potentially carrying different audio programme material. Utilising the available reflective surfaces (e.g. ceiling and walls) in nearly all domestic listening environments, these distinct beams may each be arranged to reach the listeners from different directions, thus producing surround-sound. The basic signal processing requirements as well as several refinements are described, along with a discussion of the major design parameters of practical uniform array antennas, with extensions to non-uniform and non-planar array structures.