New possibilities for the physically correct presentation of sound in three dimensions are currently being researched by Oldenburg hearing researchers Giso Grimm and Volker Hohmann. The 24-channel loudspeaker system they are testing is able to realistically simulate spatial acoustic scenes and even display movements of virtual sound sources in real time. For example, the system makes it possible to realistically simulate a road traffic situation with moving cars or shopping situations with moving background noise. The 24-channel loudspeaker system can be controlled using various playback methods such as Higher Order Ambisonics (HOA), Wave Field Synthesis (WFS) or Vector Based Amplitude Panning (VBAP). The sound fields generated in this way also allow the listener to move within the sound field, thus creating "real" 3D effects. These properties of the loudspeaker system are particularly important for tests with hearing aid wearers, as hearing aids do not function like human hearing (e.g. due to a lack of buzz localisation) and their wearers cannot properly perceive the virtual effects generated with conventional technology. In future, the loudspeaker system will be used for spatial psychoacoustics as well as for hearing aid evaluation with moving sources (e.g. precedence effect). There are also plans to use the system to research characteristic gestures in the field of "active listening" (hearing aid control through gesture recognition). Practical test with virtual acoustics (image): The generated virtual sources (shown as drawings) can be moved with the help of an "acoustic pointing stick."
[22.05.2012]