Reverberation time control by acoustic metamaterials in a small room

In recent years, metamaterials have gained considerable attention as a promising material technology due to their unique properties and customizable design, distinguishing them from traditional materials. This article delves into the value of acoustic in room acoustics, particularly small acoustics that poses specific challenges significant cavity resonant nature. Small rooms usually exhibit an inhomogeneous frequency response spectrum, requiring higher wall absorption with spectrum achieve uniform environment, i.e., constant reverberation time over wide audible band. To tackle this issue, we developed design simultaneously incorporates numerous subwavelength resonators at different frequencies customized broadband for walls example room. The on-site experimental measurements agree well numerical predictions, attesting robustness method. proposed method reverse-engineering by targeting requirements has broad applicability advantages confined spaces high requirements, such recording studios, listening rooms, car cabins.