The cross-correlation of feeding signals and spatial impression in surround sound reproduction

The relationship between the cross-correlation coefficients of feeding signals and auditory spatial impression (ASI),which are created by left,right,left surround,right surround loudspeakers in 5.1 channel surround sound system is investigated by psychoacoustic experiments.Resultsshow that,for reproducing by the front left-right or left-right surround loudspeakers pair,the auditory source width(ASW) can be broadened to some extent by controlling the cross-correlation coefficients of feeding signals.The quantitative relationships between ASW and the cross-correlation coefficients is frequency dependent.However,for reproducing by a pair of lateral loudspeakers,ASW can't be changed by controlling the cross-correlation coefficients of feeding signals.For reproducing by front and surround loudspeakers pairs simultaneously and for pink noises and octave noises with central frequencies no more than 1kHz,a strong sense of listener envelopment(LEV) can be obtained by controlling the cross-correlation coefficients of feeding signals properly. However,for the octave band noises with central frequencies at 2 kHz and 4 kHz,LEV can not be obtained by control the cross-correlation coefficients of feeding signals.Further theoretical calculations and measurements show that there isn't a unique relationship between the inter-aural cross-correlation(IACC) and ASW in 5.1 channels surround sound reproduction,which may be due to the algorithms of calculating IACC.Further experimental verifications are needed to investigate the applicability of IACC for evaluating ASI.The results will be helpful to the actual surround sound programming recording and evaluation.