Analysis of room acoustical characteristics by plane wave decomposition using spherical microphone arrays

The room acoustical characteristics have been investigated in temporal and spatial structures of room impulse responses (IRs) at different audience positions in real halls. The spherical microphone array of 32-channel is used for measurements process. Specular and diffusive reflections in IRs have been visualized in temporal domain with sound-field decomposition analysis. For plane wave decomposition, the spherical harmonics are used. The beamforming technique is also employed to make directional measurements and for the spatio-temporal characterization of sound field. The directional measurements by beamforming are performed for producing impulse responses for the different directions to characterize the sound. From the estimation of spatial characterization, the reflective surfaces of the hall are indicated as responsible for specular and diffusive reflections.