20140321679 | METHOD FOR PRACTICAL IMPLEMENTATION OF SOUND FIELD REPRODUCTION BASED ON SURFACE INTEGRALS IN THREE DIMENSIONS - A method for 3D sound field reproduction from a first audio input signal using a plurality of loudspeakers distributed over a loudspeaker surface aiming at synthesizing a 3D sound field within a listening area in which none of the loudspeakers are located with the sound field radiating from a virtual source, includes the steps of calculating positioning filters using virtual source description data and loudspeaker description data according to a sound field reproduction technique derived from a surface integral, applying positioning filter coefficients to filter the first audio input signal to form second audio input signals. Loudspeakers are positioned for a sampling of the loudspeaker surface into second loudspeaker surfaces for which the loudspeaker spacing is smaller for loudspeakers located in the horizontal plane than for elevated loudspeakers. Loudspeaker weighting data are defined from the ratio between the area covered by second loudspeaker surfaces and the total area of the loudspeaker surface. The second audio input signals are modified according to the loudspeaker weighting data to form third audio input signals, which are fed into the loudspeakers to synthesize a sound field. | 10-30-2014 |