Our Company

Day Design Pty Ltd was founded by Athol Day in 1982. Since that time we have provided "Good Acoustics by Design" to clients all over Sydney and beyond. Our reputation speaks for itself, with the majority of our work coming from repeat clients or from people who were recommended to us.

Day Design staff have amassed a wealth of theoretical and practical knowledge over the last 35 years of practice in the field of Acoustics. All of our acoustical engineers are professionally qualified and some have taken out post-graduate Masters Degrees in acoustics.

After working with Day Design for 5 years, Stephen Gauld took over as Managing Director in February 2004, ensuring that the foundation built by Athol Day continues to be built upon.

The design of acoustical enclosures and silencers for various machines requires an understanding of general engineering and building construction. Our engineers are trained to design acoustic structures that are both practical and cost-effective with due consideration being given to maintenance access and the efficient functioning of machines and buildings.


Stephen Gauld

Managing Director and Principal Acoustical Engineer
BE (Mech), MEngSc (Noise and Vibration),

William Wang

Senior Acoustical Engineer
BE (Mechatronics), MIEAust, MAAS

Thomas Roseby

Acoustical Consultant
MEngSc (Mech), MDesSc (Audio and Acoustics), MAAS

Adam Shearer

Acoustical Consultant
BCT (Audio), MDesSc (Audio and Acoustics), MAAS

Alex Mendoza

Acoustical Consultant
MDesSc (Audio and Acoustics)

Claire Fleming

Office Administrator

Quality Certified Company

Day Design is a quality certified company by SGS International Certification Services Pty Ltd to conform to AS/NZS ISO 9001:2008. Our Quality System was started and first certified in 1997.

External audits are carried out yearly in order to maintain our system. It is also regularly updated and improved each year in order to provide reliable services to our clients and to provide a uniform approach by our staff.

Acoustical Instrumentation

Day Design is equipped with a wide range of Bruel & Kjaer, Infobyte and other precision sound and vibration level meters, octave filters, third octave filters, narrow band filters, real time sound analysers, data loggers, weather logger, level recorders,statistical analysers, etc. All our acoustic instrumentation complies with the relevant Australian Standards. Calibration tests are carried out as recommended by the Standards and are traceable to National Standards.


Day Design became a member of the Association of Australian Acoustical Consultants (AAAC) in 1987. Membership is subject to academic qualifications, acoustical experience and peer review. It is the principal accreditation for acoustical consultants in Australia. Member companies are located in major cities across Australia.


Day Design is covered by workers compensation, public liability, general property and professional indemnity insurance. A current copy of our insurance certificates is available on our downloads page.

Employment Opportunities

Day Design is always looking for engineers to join the team. Click here to view our current advertisement.

  • Stephen Gauld
  • William Wang
  • Thomas Roseby
  • Adam Shearer
  • Alex Mendoza
  • Claire Fleming

Good Acoustics By Design’ is the motto behind our success in many different areas of acoustic design.

Please select one of the project headings below to take you to even more information on what Day Design can do for you.

  • Architectural
  • Environmental
  • Industrial
  • Residential