Distance perception plays an important role in 3D audio rendering. From listener’s perspective, sound intensity and direct-to-reverberant energy ratio (DRR) decrease while the distance between the listener and source increase. Though implementing changes in intensity is quite easy, providing realistic changes in direct-to-reverberant energy ratio is quite demanding.

LI Juan, YAN Yonghong of Institute of Acoustics, Chinese Academy of Sciences carried out a series of studies and proposed a new method to produce room reflections in sound field based on Wave Field Synthesis technique.

By introducing image method into Wave Field Synthesis, they derived the mathematical driving function of secondary source and proved the corresponding DRR decreases with increasing distance. We applied the proposed and traditional driving function to their loudspeaker array respectively. Compared to the method with changes only in sound intensity, their method can offer more authentic distance perception of sound source in rendered sound field. It will be a good supplement of 3D audio rendering.

This research result was published on the recently issued 2011 International Conference on Multimedia Technology(pp: 290-293).