Analysis of the acoustic response of circular electret condenser microphones

Abstract

An analysis of the average membrane deflection, sensitivity, and phase response of circular electret condenser microphones is presented. The analysis includes the influence of several parameters on the acoustic response, such as hole dimensions or air gap thickness, radiation impedance of the transducer, and viscous flow of the air in the gap and in the holes connecting the gap with the backchamber. Proper choice of the microphone parameters allows one to construct microphones for special applications.