Sound absorption of gypsum board cavity walls

Although gypsum board is probably the most common interior surface treatment in use in the United States and Canada today, the sound-absorbing properties of many common wall constructions are not well known. The results of sound absorption tests performed on several gypsum board cavity walls are reported. A calculation model was developed that accurately fits the measured data. The increased low-frequency absorption is related to the mass-air-mass resonance of the wall construction. The model also includes a residual high-frequency sound absorption component related to the properties of the exposed surface of the wall. This model can now be used to conveniently predict the sound absorption of other similar gypsum board wall constructions and to design walls with some specified minimal amount of low-frequency absorption.