Object Fusion and Localization Dominance in Real Time Spatial Processing of Acoustics Sources Using Higher Order Ambisonics

The psycho-acoustic properties fusion and localization dominance were measured for a rotating target and a fixed-position distractor, which was a delayed copy of the target. Higher-order Ambisonics was used for spatial presentation of the target. The relative delay between distractor and target, the listener position within the playback system and the angular speed of the target were varied. For measurement of the localization dominance a pointer device was developed, which allows measurement of the perceived direction in real-time, synchronized to the target motion. The aim of this study was to find the limitations of the higherorder Ambisonics setup regarding the position of listeners and sources, as well as the potential influence of source speed and continuity on these limitations. A small effect of continuity on the breakdown of localization dominance was found. The results of this study are qualitatively in line with the predictions of the precedence effect. They can directly be used to optimize an artistic concert installation where acoustic sources are processed and presented as virtual moving sources. The setup is also suited for new hearing aid evaluation methods.