Multi-Actuator Panel (MAP) loudspeakers: how to compensate for their mutual reflections?

cote interne IRCAM: VonZon04aNone / NoneNational audienceWave Field Synthesis (WFS) allows reproducing the spatial and temporal properties of a target sound field over a large listening area. Thanks to their screen shape, Multi-Actuator Panels (MAP) represent a good alternative for WFS reproduction in multimedia installations. However, MAP speakers act as reflectors for acoustic waves which disturb the perception of the target soundfield. A general listening room compensation technique is proposed, based on multichannel inversion, that allows attenuating early reflections caused by a reflector using loudspeakers integrated into this reflector (e.g. MAP loudspeakers). After an analysis of the geometrical arrangement of the panels, the method processes separately the free field equalization of the loudspeaker array and the reflection compensation. Simulation and measurements show that the attenuation is effective over the entire listening area