Audio Engineering Society

Chicago Section

Meeting Review, December 5, 2006


other meeting reports

12/05/06 Meeting Highlights
by Nick Kettman

Dave Bogema of Bruel and Kjaer spoke to the Chicago Section on December 5, 2006, on the topic of Sound Quality Measurement. Mr. Bogema currently works as an application specialist for B&K in Detroit and is responsible for product sound quality measurement and analysis products. Twenty-three local audio professionals attended the event.

Mr. Bogema began by giving his definitions of the terms �noise� and �sound.� In the context of sound quality measurement, �noise� is usually undesired and often regulated to avoid hearing damage, noise pollution, etc. �Sound,� on the other hand, is a normal and often desired characteristic of a product. Many manufacturers now engineer their products for pleasant sound quality because users take cues from the sound to determine overall product quality. For example, even if the motor in a vehicle�s powered seat is functioning normally, it can be rejected by the manufacturer on the basis of certain subjective sound qualities, such as grinding or pitch modulation, which might lead the user to believe that the motor is broken or underpowered.

One goal of Sound Quality Measurement is to relate objective measurements with subjective evaluations. The measurement process often starts with an audio recording of the product under test which undergoes subjective evaluation by humans as well as objective evaluation by audio analyzers or computer software. Based on the results of these evaluations, product designers and engineers can troubleshoot the problems and make design changes. In order to optimize this process, a precise audio recording is required. By correlating the objective results with the subjective results, the objective tests can be improved, enabling faster and more reliable results with a lesser need for human test subjects.

Mr. Bogema pointed out that much of the advanced sound quality work being done today is driven by the automotive industry, one of the first industries to incorporate engineering for sound quality in the product design process. He completed his presentation by offering several examples of products, both automotive and non-automotive, which have been engineered for sound quality. One example is a golf putter. It was discovered that the sound of a putter affected a golfer�s perception of the �feel� of the club.