Virtual reproduction of surround sound in frontal space using four loudspeakers

By considering the contribution of dynamic cue to auditory vertical localization, a method for virtual reproduction of surround sound in frontal space using four actual loudspeakers is proposed. The four actual loudspeakers are arranged in the left-front and right-front directions in the horizontal plane, as well as left-front-up, right-front-up directions in a higher elevation plane, respectively. Transaural signal processing is used to convert the multichannel sound signals to the signals for the four actual loudspeakers. Virtual reproduction of 9.1 channel sound is taken as an example. The analysis of binaural pressures and corresponding localization cues using head-related transfer functions indicates that the current method is able to recreate correct interaural time difference and its dynamic variation with head turning, and thus able to create appropriate binaural cue for lateral localization and dynamic cue for vertical localization. Results of psychoacoustic experiment indicate that the current method is able to recreate stable horizontal and vertical virtual source within the frontal-hemispherical directions. Therefore, combined with transaural processing, the four loudspeakers arrangement is enough to reproduce the vertical localization information in frontal space and realize the down-mixing and simplification of multichannel spatial surround sound. © 2020 Acta Acustica.