Improving perceived elevation accuracy in sound reproduced via a loudspeaker ring by means of equalizing filters and side loudspeaker grouping

Abstract

A spatialization method for loudspeakers arranged in a ring layout (like the one specified in the ITU recommendation ITU-R BS.775) is presented. The proposed method can be described as an improvement to amplitude panning methods in which a frequency-dependent gain is applied to mitigate the effect of loudspeaker locations on the desired signal. By grouping side loudspeakers it is possible to display elevated sources, which is difficult to achieve otherwise in single layer loudspeaker arrays. Objective evaluations showed that the proposed method produces less spectral distortion than 2D-VBAP, but degrades to cross-talk cancellation. Experimental results suggest that, despite the differences regarding cross-talk cancellation, the proposed method yields accurate azimuth and elevation estimations of sound sources in anechoic and echoic conditions except when they are located below the ear level.