Sound Pressure Level and Clipping Distortion

Distortion in microphones occurs due to limitations and other nonlinearities in a system of microphone capsule and microphone body/preamp. There are also limitations to the magnitude of sound in air. When the sound pressure level exceeds 194 dB SPL the negative part of the soundwave reaches the point of a total vacuum.

 

A major component of the microphone is microphone with its diaphragm in front of a backplate, if it is a condenser measurement microphone. The space between is in the range of a few 10 µm.

When using the microphone in a high-SPL measurement situation, it is obvious that there is a limit to the excursion of the diaphragm together with the limit to how "stretchable" the diaphragm material is in either direction.

Any condenser microphone needs an electronic amplifier or buffer stage that converts the high impedance of the capsule into a relatively low impedance to feed associated electronics and cables in between. This electronic design may be a source of non-symmetrical behavior together with the limits from the maximum microphone internal supply voltage.