Abstract: There is provided a method for controlling bass reproduction properties of a multichannel audio system, wherein the audio system has inputs for at least two audio input signals and includes a set of loudspeakers, including at least one bass-capable loudspeaker and at least two high-range loudspeakers, each loudspeaker being associated with a loudspeaker channel. The method includes obtaining impulse responses or transfer functions that represent the sound reproduction properties of each loudspeaker channel at a number of measurement or control positions. The method also includes tuning, when the audio system includes more than one bass-capable loudspeaker, loudspeaker channels of at least two bass loudspeakers to each other so that their sum impulse response has minimum spatial variability, and/or controlling high-range loudspeaker speaker channels to be in-phase with each other and/or with bass-capable loudspeaker channel in a crossover frequency band.

Abstract: There is provided a method for controlling bass reproduction properties of a multichannel audio system, wherein the audio system has inputs for at least two audio input signals and includes a set of loudspeakers, including at least one bass-capable loudspeaker and at least two high-range loudspeakers, each loudspeaker being associated with a loudspeaker channel. The method includes obtaining impulse responses or transfer functions that represent the sound reproduction properties of each loudspeaker channel at a number of measurement or control positions. The method also includes tuning, when the audio system includes more than one bass-capable loudspeaker, loudspeaker channels of at least two bass loudspeakers to each other so that their sum impulse response has minimum spatial variability, and/or controlling high-range loudspeaker speaker channels to be in-phase with each other and/or with bass-capable loudspeaker channel in a crossover frequency band.

Abstract: There is provided a method and corresponding system for determining phase adjustment filters for an associated sound generating system including at least two audio reproduction channels C1 and C2 where each of the audio reproduction channels C1 and C2 has an input signal and at least one loudspeaker located in a listening environment. The method includes estimating, for each of the audio reproduction channels C1 and C2, an acoustic transfer function at each of M?1 spatial positions in the listening environment, based on sound measurements at the spatial positions; and determining, based on the acoustic transfer functions, phase adjustment filters F1 and to be applied, respectively, to the audio reproduction channels C1 and C2, to reduce the inter-loudspeaker differential phase, IDP, between the audio reproduction channels C1 and C2 in p listener positions.

Abstract: There is provided a method and corresponding system for determining phase adjustment filters for an associated sound generating system including at least two audio reproduction channels C1 and C2 where each of the audio reproduction channels C1 and C2 has an input signal and at least one loudspeaker located in a listening environment. The method includes estimating, for each of the audio reproduction channels C1 and C2, an acoustic transfer function at each of M?1 spatial positions in the listening environment, based on sound measurements at the spatial positions; and determining, based on the acoustic transfer functions, phase adjustment filters F1 and to be applied, respectively, to the audio reproduction channels C1 and C2, to reduce the inter-loudspeaker differential phase, IDP, between the audio reproduction channels C1 and C2 in p listener positions.

Abstract: A scheme to design an audio precompensation controller for a multichannel audio system, with a prescribed number N of loudspeakers in prescribed positions so that listeners positioned in any of P>1 spatially extended listening regions should be given the illusion of being in another acoustic environment that has L sound sources located at prescribed positions in a prescribed room acoustics. The method provides a unified joint solution to the problems of equalizer design, crossover design, delay and level calibration, sum-response optimization and up-mixing. A multi-input multi-output audio precompensation controller is designed for an associated sound generating system including a limited number of loudspeaker inputs for emulating a number of virtual sound sources.