Reproduction of sound field dynamics by considering virtual acoustic impedance

Abstract

Research on sound field reproduction mainly focuses on sound signal. However, the dynamics of a sound field needs to be taken into account when sound environment information (e.g., position of walls) in the original sound field changes. This paper proposes an acoustic control system that reproduces the dynamics of the original sound field by controlling the sound source that is a loudspeaker. Sound environment information is represented as virtual acoustic impedance, which is calculated with sound propagation models that regard a reflection surface as a mass-spring- damper system. The output of the control sound source is determined by recreating the virtual acoustic impedance of a specific position in the original sound field. This enables sound environment information of the original sound field to be reproduced in reconstructed sound fields. Therefore, the proposed method is able to deal with the situation where the dynamics of sound fields changes. Finally, to validate the proposed method, a one-dimension sound field with a rubber wall as the sound environment is reproduced using the proposed method.