Patent ID: 7702111
Filing Date: 2010-04-20
Classification: H04S

Abstract:
1. A method of processing an input audio stereo signal comprising two input signals, for reproduction of a processed stereo signal in an audio stereo reproduction system comprising at least one pair of loudspeaker elements, the method comprising the steps of: a) providing a mid input signal (M) and a side input signal (S), b) producing a left output signal for transmission to a left loudspeaker in said pair, which is, or is equivalent to, the sum of the mid input signal (M) and the side input signal (S), the mid input signal (M) being attenuated by a factor α and/or the side input signal (S) being amplified a factor β, the factor α and/or β corresponding to an attenuation factor α in the range −3 dB to −15 dB; c) producing a right output signal for transmission to a right loudspeaker in said pair, which is, or is equivalent to, the sum of the mid input signal (M) and the side signal (S) phase shifted 180°, the mid input signal (M) being attenuated by a factor α and/or the side input signal (S) being amplified a factor β, the factor α and/or β corresponding to an attenuation factor α in the range −3 dB to −15 dB; the method further including the step of: at least a part of the side input signal (S) or the mid input signal (M) in the frequency range 4 kHz-9 kHz is phase shifted at least 45° but no more than 135° relative to the other signal prior to or at the production of the left and right output signals in steps b) and c).