The influence of absorbent linings on the transmission loss of double-leaf partitions

Abstract

Under certain circumstances the insertion of a porous blanket into the cavity of a double-leaf partition can produce a pronounced increase in transmission loss, particularly when the leaves have a low critical frequency and a broad coincidence plateau. In the measurements reported, improvements of between 7 and 10 dB have been obtained, depending on the size of the cavity. The authors show that a similar improvement in transmission loss is obtainable, even with quite small quantities of absorbent, if placed either round the reveals or in other limited regions in the cavity.