Preliminary testing of minimum audible angles inside a novel Ambisonics test bench

Recently, a virtual reality test bench called the “Diamonds Chamber (DC)” was completed at the Department of Engineering, University of Ferrara, Italy. An accurate reproduction of the sound directional characteristics is crucial for the usability of virtual reality test benches and the evaluation of the minimum audible angle (MAA) is used as one of the measures to qualify such directional rendering capacity. This work describes the testing procedures adopted to accomplish preliminary measurements of azimuth and elevation MAA in the DC, with a method that differs from previous literature in stimulus presentation and threshold estimation. MAA values for various azimuths lying on the horizontal plane and for 30° elevation are obtained by a 3-AFC adaptive procedure.