Sound-Field Reproduction Based on Virtual Early Reflections Using Parametric and Electrodynamic Loudspeakers

Highly realistic sound-field reproduction systems have been attracting attention owing to their ability to reproduce a sound field. These systems commonly use electrodynamic loudspeakers (EDLs) to construct sound images. The directivity of EDLs is broad, so the constructed sound images become diffused owing to the reverberation characteristics of the room. Therefore, sharp sound-image construction requires a large, complex system. As a more feasible approach, we focus on parametric array loudspeakers (PALs). The directivity of PALs is narrow, so the constructed sound image is sharp. Therefore, we propose a sound-field reproduction system that involves using a PAL to construct a sharp sound image and EDLs to reproduce the sensation of reverberation. To reproduce the sensation of reverberation, the early reflections of the target sound field are calculated using the mirror-image method, and virtual early reflections are produced. Thus, the sharpness of the sound image and the sensation of reverberation can be easily controlled to reproduce a highly realistic sound field. We conducted objective evaluation experiments to verify the effectiveness of the proposed system.