SONEX Series





  • The Q-Tech high performance SONEX circular attenuators are the outcome of a testing and development programme in our insertion loss test facility.
  • Developed to provide high performances the SONEX range is designed for several applications.
  • Their prime use is for connecting to fans, but they are also ideal for connecting to supply air grilles or being positioned anywhere throughout a system where attenuation is necessary to remove noise generated by equipment.
  • In all situations they provide a known and dependable insertion loss, giving security to design engineers looking for quality installations in often difficult to handle situations.


  • All units have been tested in accordance with BS4718:1971 for insertion loss.
  • Air flow pressure loss data was obtained from tests conducted on a BS848 : Part 1, 1980 test rig.
  • Pressure losses are little more than those which would occur over a comparable section of straight duct.


  • The attenuator consists of a perforated tubular liner manufactured from sheet steel.
  • The liner is enclosed by a thick layer of mineral wool sound absorbing material.
  • Casing and end plates are formed from galvanised sheet steel.