Full-Sphere Sound Field of Constant-Beamwidth Transducer (CBT) Loudspeaker Line Arrays

The full-sphere sound radiation pattern of the constant-beamwidth transducer circular-wedge curved-line loudspeaker array exhibits a three-dimensional petal or eyeshaped sound radiation pattern that stays surprisingly uniform with frequency. Oriented vertically, it not only exhibits the expected uniform control of vertical coverage, but also provides significant coverage control horizontally. The horizontal control is provided by a vertical coverage that decreases smoothly as a function of the horizontal off-axis angle and reaches a minimum at right angles to the primary listening axis. This is in contrast to a straight-line array, which exhibits a three-dimensional sound field that is axially symmetric about its vertical axis and exhibits only minimal directivity in the horizontal plane due to the inherent directional characteristics of each of the sources that make up the array.