Reciprocity Calibration

A method for the primary calibration of condenser pressure microphones, 1 inch and ½ inch measurement microphones, in particular. The calibration accuracy is exceptionally high, typical in the range of <0.03 dB. The method takes advantage of the fact that condenser microphones can also act as a sound source, and that the current of the source is proportional to the receiver's sensitivity. Two different methods are described and standardized: The "two-microphone" and the "three-microphone" methods.