Interaural-polar coordinate system as used in [10, 26, 27]. The lateral angle of 0° describes sources located on the median plane. The polar angle of 0° describes sources located on the horizontal plane at the eye level. Note that in this system, the lateral angle increases to the left, providing the advantage that for sources located at the eye level, the lateral angle coincides with the azimuth angle of the widely used spherical coordinate system.