PNW AES Banner

n.b. Chrome users need to refresh their browsers to ensure they have the latest content.

Meeting held Wednesday, January 8th, 2020, 7:30pm, DigiPen Institute of Technology, Redmond, Wa.

AES PNW Section Meeting Report
Old Problems, New Solutions:
Architectural Acoustics in Flux
with Ron Sauro
Owner & President
NWAA Labs Inc.
image linked to img_1778_3.jpg
PNW AES Committee Member at large Rick Chinn, Presenter Ron Sauro of NWAA Labs and PNW Section Chair Greg Dixon.
image linked to img_1759_1.jpg
Presenter Ron Sauro makes a point about transmission loss test mounts.
image linked to aes56_mach_rig2.jpg
AES 56 "MACH" Testing System: Multi Angle Computerized High Speed Testing System at NWAA Labs.

Audio recordings of the meeting:
96k mp3

Photos on this page by Gary Louie & Ron Sauro, Audio Recording by Rick Chinn


The PNW Section began the new decade with a presentation by Ron Sauro of NWAA Labs on developments in architectural acoustics. Although some would say the field is mature, Ron's research shows many familiar acoustic formulas are not as accurate as thought. The meeting, held at DigiPen Institute of Technology in Redmond, WA, drew some 36 attendees (19 being AES members).

Ron started with an in-depth biography, including colorful times playing music, serving in the military, work at NASA, earning accelerated technical degrees, and becoming involved with the EASE acoustic software development.

Ron's NWAA Labs is an advanced acoustic test facility, built in a never-quite-finished nuclear power plant in Elma, WA. Massive structure and huge spaces make his test facility among the most versatile - and quietest (non-anechoic) - in the world. For the past decade, his numerous tests of acoustic materials and properties has shown that many of the classic formulas for predicting acoustic performance of materials and construction are outdated and he has the numbers to prove it. A photo tour of the facilities showed the large arced array of microphones for tests including diffusion and scattering, and the 737 cubic-meter reverb room used for transmission loss and absorption tests.

He discussed many issues with transmission loss test mounts and tests for acoustic absorption coefficients, diffusion, and transmission loss. These were shown to be less accurate than his research numbers indicated. Diffraction and edge effects were also covered. His feeling is that the existing methods for room absorption calculations are inaccurate, and he proposes a different formula for a constant. Several "myths" about absorption were also dispelled, such as absorber arrangement, perimeter and spacing, and wall mounting of panels.

Diffusion and scattering testing also came under fire - it is a complicated effect, so the traditional information is lacking. He showed several massive 3-D particle modelling animations of diffusion tests, done by Jim DeGrandis of Acoustics First!


Reported by Gary Louie, PNW Section Secretary


Last Modified, 01/19/2020, 17:05:00, dtl