Spectrum-driven acoustic metasurface for broadband noise control

•A spectrum-driven acoustic metasurface is developed for broadband noise control.•SAM achieves targeted absorption of tonal broadband noise in a smaller size.•An inverse design method is proposed to determine the configuration of SAM.•Performance is experimentally verified by a case study on transformer noise control. To address the issue of broadband noise with tonal characteristics in indoor environments, a spectrum-driven acoustic metasurface (SAM) is proposed in this study. By combining the concept of coiled-up space with the synergetic effect between cascaded Helmholtz resonators, SAM with compact size can achieve targeted absorption of broadband noise with arbitrary tonal characteristics. Furthermore, an inverse design method based on genetic algorithms is proposed to regulate the sound absorption performance of SAM and its effectiveness is demonstrated through a case study on controlling transformer noise. Experimental results show that with a subwavelength thickness, SAM can efficiently absorb both the low-frequency noise of the transformer and the broadband noise of the cooling fans. The average sound absorption coefficient within the frequency range of 500–1000 Hz is 0.8, and reaches up to 0.85 at 100 Hz. This study provides theoretical guidance for targeted regulation of broadband noise with multiple low-frequency tonal components.