Acoustics · Vibration · Expert evidence
Independent acoustic expertise, backed by measurement.
The Acoustic Group provides specialist noise and vibration assessment, research and expert evidence. Led by Steven Cooper, the firm brings four decades of field work to projects ranging from helipads and military jets to wind farms, heavy industry and the courts.
1982
Consulting in acoustics and vibration since 1982
AS 2021
Convener of Appendix C and contributor to AS 2021 and AS 2363
60+
Helipads evaluated across Australia
1997
Engineering Excellence Award, Institution of Engineers
What we do
Specialist services
Every assessment starts with physical measurement, using instrumentation selected for the job — including multi-channel and infrasound-capable systems tested in our own hemi-anechoic room.
Aviation & Defence
Helicopter and fixed-wing noise, NPD curve derivation, INM validation, ANEF review and noise and flight-path monitoring for civil and military aerodromes.
Wind Farms & Infrasound
Infrasound and low-frequency noise measurement using specialist instrumentation, the Wind Turbine Signature, community impact studies and compliance reviews.
Industrial Noise & Vibration
Sound power surveys, noise-source ranking and long-term noise reduction programs for petrochemical, manufacturing and processing plants.
Legal Assignments
Independent acoustic evidence before Local, Land & Environment, District, Supreme and Federal Courts — for applicants, authorities or as the court’s expert.
Expert Witness
Joint expert reports, peer review of acoustic assessments and clear, measurement-based testimony on noise and vibration disputes.
Licensed Premises & Venues
Noise assessment and design for hotels, clubs, music venues, festivals, theatres, studios and auditoria.
Aviation & Defence
Australia’s reference point for aircraft noise verification
Steven Cooper’s testing of Australian military aircraft led to the 2008 Joint Strike Fighter noise program at Edwards AFB, California — identified as the most comprehensive noise testing of any military aircraft. After he presented a correction to the US SAE A-21 committee, the Integrated Noise Model was modified for helicopter operations.
- Noise verification and NPD testing for the F-111, FA-18, Super Hornet, Hawk, JSF, Tiger, MRH90 and more
- Noise and Flight Path Monitoring certification for RAAF and RAN bases
- Author of the Australian Helicopter Fly Neighbourly Guide
Research
The Wind Turbine Signature
Using instrumentation well beyond standard sound level meters, our testing identified a periodic signature in the infrasound region below 20 Hz: the blade-pass frequency and its harmonics. The pattern has been measured at operating wind farms, at affected homes and inside dwellings — and it disappears when the turbines stop.
The 2014 Cape Bridgewater study, carried out with the full cooperation of the wind farm operator and residents, proposed the dB(WTS) metric to support further research.
Our testing revealed the presence of a periodic signature in the infrasound region, being frequencies below 20 Hz.
Steven Cooper, The Acoustic Group
Latest
Projects & news
-
Welcome to the new Acoustic Group website
Our website has been rebuilt with a refreshed design, an updated publication list and a new library of free whitepapers.
Need an independent acoustic assessment or expert opinion?
Talk to Steven Cooper about your project, dispute or compliance question.