Circular electret microphones : Theoretical and experimental investigations

Theoretical and experimental investigations of the acoustic frequency response of circular backplate electret microphones are discussed. In particular the sensitivity to air-borne sound and the vibration sensitivity of the transducers are studied for different parameters such as membrane tension and radius. Furthermore, the influence of hole geometry of the backplate and the effect of ambient pressure on the microphone damping. Measured and calculated responses show very good agreement.