Investigation of realistic acoustic scene simulation for people with hearing impairment
Master Thesis of Stockmann, Anne
The auralization of complex everyday life situations has been investigated for quite some time. A system for simulating virtual acoustic environments (VAE) is currently being developed and explored at the Institute of Technical Acoustics (ITA) at the RWTH Aachen University. Simulation of such room acoustic environments has potential for a variety of useful medical applications, such as the evaluation of new hearing aids and hearing aid algorithms. Furthermore, this technology may provide assistance to the individual ?tting of hearing aids performed by audiologists. To further the use of VAE into the clinical population, this thesis presents the results of 1) an investigation of a realistic acoustic scene suitable for future simulation from in situ measurement and 2) a validation of a loudspeaker-based binaural playback system using a sound localization task. To enable the playback of virtual scenes for the hearing impaired, a set of research hearing aids was recently integrated into the VAE system. This setup is intended for simulating di?erent everyday life situations for individuals with hearing impairment, including school children. This thesis ?rst focuses on the room acoustic and psychoacoustic parameters in classrooms from in situ measurements, which provide input on the simulation of realistic acoustics in future studies for children. The room acoustics measurements took place in unoccupied classrooms at a school for children with educational needs in hearing and communications. Activities during lessons and lunch breaks were also recorded and analyzed. The second part of the present work evaluates the loudspeaker-based binaural playback system for auralization through normal hearing adults’ performance of localization of virtual sound sources. The data is compared to the results of a previous localization study using virtual sound sources played via headphones and real sound sources.