An investigation into the mechanism of sound-energy absorption in a low-frequency modular absorber

摘要

An investigation into the behaviour of a widely used type of modular, low-frequency acoustic treatment is described. A region of spurious sound-energy absorption in the middle part of the audio frequency range, which was originally acceptable, has become more significant in units made since the prototypes were tested in 1969. This has caused excessive absorption in treated rooms in this range of frequencies.nIn an effort to identify the cause of this spurious absorption, a theoretical study was carried out, based on the supposed behaviour of this absorber. This analysis failed to identify the cause, showing that the supposed behaviour was erroneous.