Room acoustics modelling and auralizations are very useful tools in the design of acoustically sensitive spaces. One area of improvement for auralizations is the method of modelling the source directivity. A new method to incorporate source directivity is multi-channel auralizations. This study first evaluates the objective effects of using four and thirteen channel impulse responses in an ODEON model of Queen’s Hall, where the actual variable absorption is changed within the model. Analyses of the results reveal great differences in the objective parameters of reverberation time and sound pressure level across each channel’s impulse response. Subjective studies were then conducted to see the effect on multi-channel auralizations of changing source orientation with different amounts of absorption in the modelled room. A significant effect of orientation was not found when subjects were asked to rate the clarity of the auralizations, but clarity ratings were significantly related to room absorption. When asked to rate the listener envelopment, subjects did differentiate between orientations, identifying auralizations with the source facing the audience as sounding more enveloping than when the source faced away. The listener envelopment ratings were also correlated with the calculated late lateral level values. The subjective ratings decreased as the absorption in the room decreased.
Available at: http://works.bepress.com/lilymwang/28/