Spatial sound reproduction using conventional and parametric loudspeakers

The auditory image of a movie or game scene can be decomposed into point-like sources and diffused sources for effective and accurate audio synthesis. By embedding appropriate visual and audio cues into objects in a 2D or 3D visual scene, an immersive and engaging experience can be created. While there are many breakthroughs in the display technology recently, such as the ultra high-definition (UHD) and 3D displays, conventional sound systems (stereo, 5.1, etc) are still being used. Such an audio-visual setup may degrade the overall experience. This degradation is directly linked to the dispersive nature of the conventional loudspeaker, and the rendered auditory image may be perceived to lack sharpness in the spatial imaging due to the reverberant nature of a room. This drawback tends to lead to comparably poor synthesis of point-like sources as compared to diffused sources in the rendered auditory image. On the other hand, the rendered auditory image from a directional loudspeaker, such as the parametric loudspeaker, may seem to lack spaciousness and sound envelopment due to very little influence of the acoustics of a room. Therefore, directional loudspeaker is suitable for rendering point-like sources, but not diffused sources. In this paper, we propose a unique sound system which comprises of conventional loudspeakers and parametric loudspeakers. This setup exploits the high directivity of the parametric loudspeakers to render sharp auditory images while producing the diffused sources of the auditory image using the conventional loudspeaker.