Abstract
The transient response of an electret microphone without a back cavity (i.e., with no cavity below the back electrode which communicates with the air trapped between the foil and the back electrode) is analyzed by examining the motion of the electret foil in response to a transient acoustic signal applied uniformly on the foil face. The analysis uses a normal mode expansion of the motion of the circular diaphragm. A numerical evaluation of the time domain response of the electret microphone based on the analysis is pressented for the acoustic excitation by an N-wave (i.e., shock wave). Results for the N-wave show good agreement with experimental measurements. both in motion of membrane and output voltage.
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Cho, W. Transient response analysis of an electret microphone. KSME Journal 5, 71–78 (1991). https://doi.org/10.1007/BF02953604
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DOI: https://doi.org/10.1007/BF02953604