A NOISE ATTENUATION DEVICE

摘要

A noise attenuation device comprises an array of quarter-wave resonators, including at least two sets of resonators typically tubes which are rectangular or circular cross section, with the resonators in each set being tuned to a resonant frequency. The resonators in each set are tuned to a resonant frequency different to those of other sets in the array. The attenuation device may be positioned in or adjacent a noise pathway, or over part of a noise pathway, in a structure separating a first and a second area such as a ventilation hole linking the interior and the exterior of a building or the like.