Paper perforated gypsum board is often used for sound absorption in architectural decoration. The paper-faced gypsum board itself does not have good sound absorption performance, but after being perforated and installed into a suspended ceiling or veneer wall with a certain back cavity, it can form a "Helmholtz resonance" sound absorption structure, thus obtaining a larger The sound absorption capacity. This paper-surface perforated gypsum board sound-absorbing structure is widely used in acoustic engineering such as hall sound quality and sound absorption and noise reduction.

After the gypsum board is perforated, the small holes in the gypsum board and the gypsum board itself and the surface layer of the original building structure form a resonance cavity. After the sound interacts with the perforated gypsum board, the air column at the circular hole produces a strong resonance, and the air molecules Vigorously rubs against the wall of the gypsum board hole, which consumes a large amount of sound energy and absorbs sound.

　　 This is the basic principle of "Helmholtz resonance" sound absorption in perforated plasterboard. The sound absorption of perforated plasterboard has a certain selectivity to the sound frequency, and the sound absorption frequency characteristic curve is in the shape of a mountain. When the sound frequency is close to the resonance frequency, the sound absorption coefficient is large; when the sound frequency is far away from the resonance frequency, the sound absorption coefficient is small . If the paper perforated gypsum board is covered with a layer of mulberry paper or thin sound-absorbing felt, the frictional resistance of air molecules at resonance will increase, and the sound absorption performance of each frequency will be significantly improved. This is why people often use perforated paper. The plasterboard is covered with a layer of mulberry paper or thin sound-absorbing felt to increase the sound absorption. The main factors affecting the sound absorption performance of the paper perforated gypsum board are the perforation rate and the size of the back cavity. The perforation hole diameter and the thickness of the gypsum board have little effect on the sound absorption performance. When the perforation rate gradually increases from 2% to 15%, the surface area occupied by the holes increases, and the probability of air molecules entering the resonance cavity to participate in resonance increases, and the sound absorption capacity increases. If sound absorption materials are placed in the back cavity , The sound absorption is stronger. The perforation rate will affect the resonance frequency. As the perforation rate increases, the resonance frequency will shift to high frequency. The offset is proportional to the root of the perforation rate. As the perforation rate increases, the "mountain" of the sound absorption frequency characteristic curve will move to the right (high frequency), and the overall shape of the "mountain" tends to rise, and the average sound absorption coefficient increases. Increasing the perforation rate can improve the sound absorption performance, but due to the limitation of the strength of gypsum board, the general perforation rate is in the range of 2%-15%.