@conference {130, title = {A Compact 120 Independent Element Spherical Loudspeaker Array with Programmable Radiation Patterns}, booktitle = {Audio Engineering Society 120th Convention}, year = {2006}, pages = {Convention Paper No. 6783}, address = {Paris, France}, abstract = {We describe the geometric and engineering design challenges that were overcome to create a new compact, 10-inch diameter spherical loudspeaker array with integrated class-D amplifiers and a 120 independent channel digital audio interface using Gigabit Ethernet. A special hybrid geometry is used that combines the maximal symmetry of a triangular-faceted icosahedron with the compact planar packing of 6 circles on an equilateral triangle ("billiard ball packing"). Six custom 1.25inch drivers developed by Meyer Sound Labs are mounted on each of 20 aluminum triangular circuit boards. Class D amplifiers for the six speakers are mounted on the other side of each board. Two pentagonal circuit boards in the icosahedron employ Xilinx Spartan 3E FPGA{\textquoteright}s to demultiplex digital audio signals from incoming Gigabit Ethernet packets and process them before feeding the class-D modulators. Processing includes scaling, delaying, filtering and limiting.}, url = {http://cnmat.berkeley.edu/publication/compact_120_independent_element_spherical_loudspeaker_array_programmable_radiation_patterns}, author = {Rimas Avizienis and Freed, Adrian and Kassakian, Peter and Wessel, David} }