AES New York 2009
Sunday, October 11, 5:00 pm — 6:30 pm
T4 - Electroacoustic Measurements of Headphones and Earphones
Christopher J. Struck, CJS Labs - San Francisco, CA, USA
This tutorial reviews basic electroacoustic measurement concepts: gain, sensitivity, sound fields, signals, linear, and non-linear systems. The Insertion Gain concept is introduced. The orthotelephonic response is described as a target for both the free and diffuse fields. Equivalent volume and acoustic impedance are defined. Ear simulators and test manikins appropriate for Circum- Supra- and Intra-aural earphones are presented. The salient portions of the IEC 60268-4 standard are reviewed and examples are given of the basic measurements: Frequency Response, Distortion, Impedance. A brief introduction to Noise Canceling devices is also presented.