When it comes to acoustic solutions, performance is everything. Whether you’re developing products or environments designed to enhance the listening experience, minimizing interference from outside noise and vibration, creating ideal conditions for sound recording, ensuring precise audio measurement, or maximizing the insulating and privacy characteristics of building materials – ETS-Lindgren is the partner that consistently delivers the solutions you need.
ETS-Lindgren acoustic solutions are backed by more than 40 years of experience in acoustics and engineering. Our experts work with you and your team of integrators, architects, engineers, and designers to create optimal test environments, designed specifically to meet the precision requirements of different industries and applications:
Historically, anechoic and hemi-anechoic chamber qualification has been defined in ISO 3745 Annex A. In 2012 an independent standard for anechoic and hemi-anechoic chamber qualification, ISO 26101, was initially released. The presentation will compare and contrast the two standards and their current states. The impact of the changes on existing chambers and future chamber design will be presented.
Douglas Winker and Brian Stahnke
How well do you know your windows If you have never tested them at an acoustical testing laboratory, you probably dont know them as well as you should. The information gained from acoustical testing is an essential part of architectural specifying and manufacturing and can have an impact on your clients satisfaction, contracts, and bottom line. Testing shows the acoustical performance of your window and easily identifies leaks and underperformance that can lead to unhappy customers and possibly legal actions. So what do you need to know to get your moneys worth out of acoustical testing Read the article for ten tips to ensure a successful acoustical test experience.
Brian Stahnke and Dr. Douglas Winker
Engineering-grade product noise emission testing programs using a hemi-anechoic chamber are qualified, and correction factors are applied to test results, based upon known sound power levels of a reference sound source; i.e., a sound source that has been tested and qualified in accordance with ANSI S12.5/ISO 6926.
Michael C. Black and Einar Gibbens Ristroph
Consumer product noise emission testing is often conducted using standardized test methods such as ISO 3744 or ISO 3745. Both standards outline a method of averaging sound pressure levels over a known surface area enveloping the specimen in a free-field environment to determine sound power levels. When the device under test is small (the case for many consumer products), a hemispherical measurement surface in a hemi-anechoic chamber is often used. An assumption is made that the source location is the center of the hemisphere and thus only direct sound energy encounters the measurement surface. In practice, the actual center of measurement surface is located in the floor plane, and the actual product to be tested is placed above the floor plane.
Douglas F. Winker, Ankit Chadha and Einar G. Ristroph
Two commonly used methods for determining sound power levels a reverberation chamber method and a hemi-anechoic chamber method are compared, with respect to correlation of determined results as well as practical considerations (test time, measurement instrumentation required, and chamber configuration).
Einar Gibbens Ristroph