抄録
In this paper, we investigate loudspeaker array directivity control and its application to sound localization when steering the beam direction of the loudspeaker array. The filter of a spherical loudspeaker array is designed based on the minimum variance (MV) method [1] in the spherical harmonics (SH) domain [2]. The beam pattern generated by the filter achieves a high directivity in a certain direction. Further, the beam direction can be rotated while maintaining the shape of the beam pattern. We implemented a prototype system that allows the listener to steer the beam direction using a gyro sensor in real time. The listening test result suggested that the location of the sound image varies based on the sound reflected from the wall. We evaluated the sound localization mechanism while rotating the beam direction based on the observed signal measured with a dummy head. The result showed that the sound of the beam reflected from a wall influences horizontal plane localization and sound image distance.