Abstract:

The growing interest in multimedia raises questions like how to present 3-D sound to the user of a multimedia system. Such presentations should not necessarily be exact replicas of the real-life experiences; however, they should still provide a quality that convinces the user of being present in the acoustical environment intended. This paper briefly introduces an alternative method of ray tracing that indeed is simplified compared to that of the conventional ray-tracing/mirror-image approach. The method may be considered as a space discretized version of ray tracing and it is considerably faster than the latter. In order to reveal subjective differences between the two methods, a psychoacoustical listening experiment was carried out using binaural synthesis. Twenty subjects participated and in two sessions they were asked to rate coloration and reverberation, respectively, by clicking a mouse---each time listening to a music or speech sound frame. In a third session a sketch of a room and the position of the subject were shown, and the subjects were asked to indicate from what position the sound appeared. The sounds were produced using the new method and traditional ray tracing. The results from the listening experiment are presented in the paper.