Sound Attenuators

Acran Sound Control › Noise Control Products › Sound Attenuators

Sound attenuators are sound-absorbing devices used to reduce the level of noise produced by mechanical equipment and other sources of noise in industrial and commercial settings—including through ventilation ducts and other pathways.

Sound attenuators are commonly used in a variety of applications, including HVAC systems, power generation facilities, and cooling systems. They are an effective way to control noise levels and improve the working conditions for employees, while also reducing the impact of noise pollution on the surrounding environment.

The attenuators are engineered and manufactured by Acran Sound Control to allow passage of air while reducing the noise level along the air path. They are custom manufactured in-house to suit each individual customer application and are not restricted to meeting module sizes. It’s this bespoke manufacturing process that enables maximum flexibility when balancing the space requirement with the acoustic and airflow restraints.

Main applications


  • Plant room ventilation
  • Ventilation to acoustic enclosures
  • Air conditioning installations and cooling towers
  • Silencers for exhaust fans
  • Power generation equipment
  • Outdoor air ventilation systems
  • Refrigeration plant
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Attenuators performance data

Acraflow Rectangular Attenuators: M3ST

*Tested in accordance with AS 1277-1983



 Static insertion loss (dB*)
Length (mm) 63 125 250 500 1000 2000 4000 8000 Hz
900 4 7 18 34 43 38 22 14 dB
1200 6 10 23 40 47 42 28 17 dB
1500 6 16 32 42 48 42 32 20 dB
2400 10 28 38 46 52 50 43 28 dB


Acraflow Rectangular Attenuators: M4ST

*Tested in accordance with AS 1277-1983



 Static insertion loss (dB*)
Length (mm) 63 125 250 500 1000 2000 4000 8000 Hz
900 4 6 16 31 40 36 17 11 dB
1200 5 10 21 39 46 41 23 14 dB
1500 5 11 27 42 46 41 26 16 dB
2400 9 19 38 46 48 47 39 26 dB


Acraflow Rectangular Attenuators: M6ST

*Tested in accordance with AS 1277-1983



 Static insertion loss (dB*)
Length (mm) 63 125 250 500 1000 2000 4000 8000 Hz
900 3 6 12 24 30 21 12 9 dB
1200 4 7 18 31 36 27 14 10 dB
1500 5 10 21 38 43 33 19 13 dB
2400 7 14 34 46 47 45 28 19 dB


Acraflow Rectangular Attenuators: M8ST

*Tested in accordance with AS 1277-1983



 Static insertion loss (dB*)
Length (mm) 63 125 250 500 1000 2000 4000 8000 Hz
900 3 4 10 20 24 15 9 6 dB
1200 3 5 15 26 29 19 11 8 dB
1500 4 7 18 33 37 24 12 9 dB
2400 7 11 31 47 49 37 15 11 dB


Design features

  • Excellent noise reduction for use of space
  • Choices of materials and finishes provided
  • Manufactured to connect to standard ductwork connections
  • Supplied in module form allowing large openings to be infilled
  • Vermin mesh screens and matching fixing angles available as optional extras

Product benefits

  • Guaranteed performance: tested to Australian Standards
  • Wide range of flanging options including TDC/TDF
  • Cost effective with long life and low maintenance
  • Sturdy construction designed to suit all applications

Completed projects

  • ABC Studios, Southbank Brisbane
  • Cairns Base Hospital: air-conditioning plant room
  • Ferny Grove Tavern: refrigeration plant
  • QGC: gas engine enclosure

Product brochure

Attenuators product brochure

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Engineering process

We design and manufacture bespoke noise control and ventilation solutions for your specific commercial or industrial premises.

Acran Sound Control provides highly specialised expertise and experience, engineering prowess with in-house Australian manufacturing, highly trained installation teams, and bespoke project management.

Our bespoke engineering process:

If your business or project needs to control noise or implement ventilation, we will engineer, manufacture and install a bespoke solution designed just for you.


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