Virtual quiet zone method for sound zone reproduction in coupled rooms

Sound zone reproduction aims to deliver sound to target listeners in the listening zone while reducing unwanted sound for others in the quiet zone. Existing approaches primarily focus on reproducing sound zones within a single room. When employing existing methods in coupled spaces, the accurate measurement of cross-room acoustic transfer functions (ATFs) poses significant challenges. This paper proposes a virtual quiet zone method to improve sound zone performance in coupled rooms. The proposed method eliminates the need for complex cross-room ATF measurement. We use the Improved Grey Wolf Optimizer to establish an appropriate virtual quiet zone within the virtual space based on the measured sound pressures at the zones. The ATFs between the loudspeakers and the virtual quiet zone can be interpolated utilizing acoustic modeling and the measured ATFs between the loudspeakers and the listening zone. In the proposed algorithm, the optimization of sound zone reproduction in coupled rooms is transformed into the optimization of the position of the virtual quiet zone within the virtual space. Experimental results show that the proposed method outperforms the current acoustic contrast control method and brightness control method in real-world implementations in coupled rooms.