Simplified Three-Microphone Acoustic Test Method

Abstract

Accepted acoustic testing standards are available; however, they require specialized hardware and software that are typically out of reach economically to the occasional practitioner. What is needed is a simple and inexpensive screening method that can provide a quick comparison for rapid identification of the top candidates. This research reports on the development of an acoustical rapid-test method that achieves these objectives. The method is based upon a reformulation of the well-regarded three-microphone method. The new formulation reduces the number of required microphones to a single microphone and removes the need for simultaneous capture and extensive signal-processing analysis. The study compares the proposed simplified method to two standard methods and the three-microphone method. The results of the correlation analysis between the new method versus the original method produced a coefficient of determination of r 2 = 0.994. A simulation study highlighted several unique accuracy advantages of this new proposed method in comparison to the existing standard methods. The proposed new method represents an easy-to-use technique that requires little in the way of equipment and can be set up with minimal training and expense.