Interactive reproduction of virtual acoustic environments for the evaluation of hearing devices—Methods and validation

Abstract

Virtual acoustic environments are increasingly used for evaluating hearing devices in complex acoustic conditions. In this talk we propose an interactive simulation method via multi-channel loudspeaker systems or headphones. The method focuses on the time-domain simulation of the direct path and a geometric image source model, which simulates air absorption and in case of motion the Doppler effect of all primary and image sources. To establish the feasibility of this approach, the interaction between reproduction method and technical and perceptual hearing aid performance measures was investigated using computer simulations. Three spatial audio reproduction methods were compared in regular circular loudspeaker arrays with 4 to 72 channels. The influence of reproduction method and array size on performance measures of multi-microphone hearing aid algorithms was analyzed. In addition to the analysis of reproduction methods, algorithm performance was tested in a number of different virtual acoustic environments in order to assess the underlying factors of decreased hearing aid performance in complex environments. The results confirm previous findings that spatial complexity has a major impact on hearing aid benefit, and demonstrate the potential of virtual acoustic environments for hearing aid evaluation. [Funded by DFG FOR1732 “Individualized hearing acoustics.”]