Compact Spherical Loudspeaker Array
Rimaz Avizienis, Adrian Freed, Peter Kassakian, John MacCallum, Andrew Schmeder, David Wessel, Franz Zotter
The research team at The Center for New Music and Audio Technologies, in collaboration with Meyer Sound of Berkeley CA, has created a compact 120-channel approximately spherical loudspeaker for experiments with synthesis of acoustic signals with real-time programmable directional properties. These directional patterns can reproduce the complete radiative signature of natural instruments, or explore new ideas in spatial audio synthesis.
The array has 120 independently controlled 1-inch diameter loudspeakers. It is interfaced to a computer using gigabit ethernet and appears as a system audio device with 120 output channels. The entire array is approximately 20 cm in diameter and can be pole-mounted or suspended overhead. For full-bandwidth reproduction, audio frequencies below 500 Hz are sent via crossover to a reinforcement sound system. The control of the system is accomplished using the theory of spherical harmonics, and is capable of easily producing patterns up to order 5.