The Perceptual Effects of Horizontal and Vertical Interchannel Decorrelation, using the Lauridsen Decorrelator

The perceptual effects of interchannel decorrelation, using a method proposed by Lauridsen, have been investigated subjectively, looking specifically at the frequency dependency of decorrelation. Twelve subjects graded the perceived auditory image width of a pink noise sample that had been decorrelated by a Lauridsen decorrelator algorithm, varying the frequency-band, time-delay and decorrelation factor for each sample. The same test has been carried out in both the horizontal and vertical planes. Results generally indicate that decorrelation is more effective horizontally than vertically. For horizontal decorrelation, the higher the frequency, the more effective the decorrelation, with a longer time-delay required for lower frequencies. In contrast, the vertical width produced by vertical decorrelation is better perceived at lower frequencies than higher ones.