Patent ID: 7292696

Claim:
An electret condenser microphone comprising an electro-acoustic transducer (M) having an electret portion (E) having at least one of a diaphragm ( 6 ) acting as an electrode and a stationary electrode ( 2 , 25 ) disposed in opposition to the diaphragm ( 6 ), and a FET ( 10 ) effecting an impedance conversion on an output from the electro-acoustic transducer (M) and outputting the converted output on a signal line (L), wherein: said FET ( 10 ) comprises a MOS type; a capacitor ( 11 ) and a varistor ( 12 ) are provided in parallel between said signal line (L), which is coupled to one output terminal (D) of said FET ( 10 ), and a ground ( 18 ) coupled to the other output terminal (S) of said FET ( 10 ); and a resistor ( 13 ) is incorporated in series in said signal line (L).