There is a range of sound attenuators now available from Fantech . Sound Bar Attenuators are sheet metal louvres with acoustic properties commonly used to reduce the noise level from plant rooms escaping to outdoors.
Circular Attenuators are high performance and are of an ultra-light construction. They can be mounted directly to the fan, before the outlet grille or anywhere in the system where their application will reduce the ambient noise level. They are usually bolted to a fan or to ductwork and are designed to reduce the noise level in occupied areas to acceptable levels.
Rectangular Attenuators are available in a wide range of dimensions. They are rectangular sheet metal ducts with internal acoustic splitters which are usually bolted to ductwork. They are designed to reduce the noise level in occupied areas to acceptable levels.
Cross-Talk Attenuators are rectangular sheet metal ducts with acoustic absorbing material. They are designed to reduce the noise transferred from room to room via an air transfer duct.