This independent black box theater hosts small dramas, poetry readings and intimate live music performances. The compact enclosed space suffered from severe low-frequency reverberation and uneven sound field, resulting in muddy speech and a lack of detail in musical performances. As a multi-functional performance venue, it needed flexible acoustic performance that could adapt to both spoken word and live music, and standard acoustic products could not meet the professional acoustic index requirements of a performance space.

We designed a customized grooved and perforated resonant acoustic system for the side and rear walls of the theater. Based on the Helmholtz resonance principle, we adjusted the hole and slot ratios according to the venue’s volume and usage scenarios, precisely targeting the 250Hz–1000Hz mid-low frequency standing waves that commonly plague small performance spaces. Combined with rear air cavities and acoustic filling, the system achieves an overall NRC of 0.90 for balanced full-band sound absorption. Custom wood veneer finishes match the theater’s dark, immersive interior style.

Upon completion, the theater’s reverberation time fell into the optimal range for both drama and small-scale music performances. Speech intelligibility improved dramatically, and musical performances present clear layers and full dynamics. The theater director commented that the venue now supports diverse performance forms without additional temporary acoustic treatment, greatly improving venue utilization and audience experience. The custom resonant structure enables precise frequency control, balances acoustic performance for different performance types, and integrates seamlessly with the theater’s immersive interior design.