Mechanical characterization of capacitor microphones for analysis and study.
YuFan Chuang, S. J. Pawar, Jin H. Huang · The Journal of the Acoustical Society of America · 2009
An attempt is made to investigate the mechanical properties of the diaphragm of capacitor microphone using MTS Tytron 250 micro-force testing machine. The compliance of the diaphragm is calculated from the force-displacement diagram. The simulation of the microphone is carried out using equivalent circuit method. The mechanical parameters like mass (measured), compliance (measured and calculated), and resistance (assumed from literature) are being used to formulate mechanical domain of microphone in equivalent circuit model. The sensitivity curve of microphone is being plotted. Simultaneously, the experimental measurement has been carried by PULSE Electroacoustics with the software Sound Check in an anechoic chamber. The simulation and experimental results for sensitivity are found to follow each other within a wide frequency range. The characteristic investigation is carried out using validated equivalent circuit model for parametric study of microphone. [Work supported by Contract Nos. NSC 95-2221-E-035-013-MY3 and 95-2221-E-035-087. The authors would like to thank Leo Liao and Jack Wei of Merry Electronics Co. Taiwan and Listen Inc. for supplying Sound Check measurement.]