Models predicting the perceptual externalization of sound sources

Overview & Synopsis

Perceptual externalization denotes the ability to associate sensations with external objects. In the auditory modality, sound sources are usually perceived externalized in natural listening situations whereas headphone playback often results in unrealistic sound images localized inside the listener?s head. Binaural synthesis, as commonly used in virtual and augmented reality systems, aims to reproduce sound sources as realistically as possible. An extensive evaluation of such systems is often rendered unfeasible whenever time-consuming listening tests become required. Prediction models can support the development process immensely at this stage and further deepen our understanding of the mechanisms underlying auditory externalization. In this talk we will present a phenomenological model for predicting perceived externalization of static sound sources. We assessed the predictive performance of the model against externalization ratings from several previous psychoacoustic experiments. We further used the model to evaluate the perceptual contribution of different acoustic features, enabling us to discuss various potential combination strategies applied by the auditory system to infer spatial attributes of the environment.