Abstract: The invention provides a method for generating output filters to a plurality of loudspeakers at respective positions for playback of a plurality of different input signals in respective spatially different sound zones by means of a processor system. The method comprising computing spatio-temporal correlation matrices in response to spatial information, e.g. measured transfer functions, and in response to desired sound pressures in the plurality of sound zones. Joint eigenvalue decomposition of the spatial correlation matrices are then computed, or at least an approximation thereof, to arrive at eigenvectors accordingly. Next, variable span filters a reformed from a linear combination of the eigenvectors in response to a desired trade-off between acoustic contrast and acoustic errors in the sound zones. Finally, output filter for each of the plurality of loudspeakers, for each of the plurality of input signals, in accordance with the variable span filters.

Abstract: The invention provides a method for generating output filters to a plurality of loudspeakers at respective positions for playback of a plurality of different input signals in respective spatially different sound zones by means of a processor system. The method comprising computing spatio-temporal correlation matrices in response to spatial information, e.g. measured transfer functions, and in response to desired sound pressures in the plurality of sound zones. Joint eigenvalue decomposition of the spatial correlation matrices are then computed, or at least an approximation thereof, to arrive at eigenvectors accordingly. Next, variable span filters a reformed from a linear combination of the eigenvectors in response to a desired trade-off between acoustic contrast and acoustic errors in the sound zones. Finally, output filter for each of the plurality of loudspeakers, for each of the plurality of input signals, in accordance with the variable span filters.

Abstract: A method for estimating a distance between a first and a second loudspeaker characterized by playing back a first stereo source signal vector s1 on the first loudspeaker, and playing back a second stereo source signal vector s2 on the second loudspeaker, acquiring a first recorded signal vector x1, using a first microphone arranged adjacent to the first loudspeaker, and acquiring a second recorded signal vector x2 from a second microphone arranged adjacent to the second loudspeaker, wherein x1 and x2 are N-dimensional vectors, setting the distance equal to ?v/f, where v is the speed of sound, f is the sampling frequency, and ? is an estimated sample delay of a source signal played back on one of the loudspeakers and a recording acquired by a microphone at the other loudspeaker.

Abstract: A method for estimating a distance between a first and a second loudspeaker characterized by playing back a first stereo source signal vector s1 on the first loudspeaker, and playing back a second stereo source signal vector s2 on the second loudspeaker, acquiring a first recorded signal vector x1, using a first microphone arranged adjacent to the first loudspeaker, and acquiring a second recorded signal vector x2 from a second microphone arranged adjacent to the second loudspeaker, wherein x1 and x2 are N-dimensional vectors, setting the distance equal to ?v/f, where v is the speed of sound, f is the sampling frequency, and ? is an estimated sample delay of a source signal played back on one of the loudspeakers and a recording acquired by a microphone at the other loudspeaker.