Amplitude panning-based sound system for a horizontal surface computer: A user-based study

Given the growing popularity of multi-touch mobility devices (e.g., iPods, smartphones), the move to multi-user touch screens and horizontal surfaces is a likely trajectory of the technology. Before smart tables become widely accepted, there are many questions particularly with respect to sound production and reception and multi model interaction for these devices that need to be explored (i.e., the interaction of sound and video cues). With respect to the sound interface, this introduces several design issues that must be addressed. More specifically, where do we position the loudspeakers and where should we position sounds in the mix, (in which speaker) for best reception? Here we describe a simple, and computationally efficient bilinear interpolation-based amplitude panning method designed specifically for horizontal surface computers with four loudspeakers. Preliminary user-based experiments were conducted to test the effectiveness of the method. Preliminary results indicate that virtual sound source positions very close to the user lead to the greatest localization error while the localization error for virtual sound source positions along the border of the surface was less.