Binaural synthesis adjusting a simple gain and delay based on the two-channel optimal source distribution

Two-channel optimal source distribution is a binaural synthesis technique over loudspeakers that utilizes a pair of conceptual sound sources whose azimuthal location varies continuously as a function of frequency. Discretized arrangement of sound sources with appropriate frequency ranges makes it possible to realize practical systems based on the principle. As a result, the inverse matrix derived from a plant matrix of the discretized system including the head-related transfer functions is well conditioned to satisfy equalization of the reproduction transfer function and crosstalk cancellation simultaneously. In this paper, the authors proposed a simplified technique of binaural synthesis over loudspeakers using the discretized optimal source distribution arrangement that emphasizes only crosstalk cancellation and not equalizes the reproduction transfer function. This can be accomplished by adjusting only a relative gain and delay representative of each frequency range in the discretized sound sources. The proposed system is likely to enhance an immersive spatial impression even for sound sources not having spatial information from head-related transfer functions, such as stereo sound sources.