MN4229high sound pressure microphone is 1/4 inch prepolarized pressure field microphone that uses IEPE power  supply and does not require polarization voltage. The preamplifier housing is made of stainless steel material and is  suitable for pressure field environments such as in cavities, near hard reflective surfaces, or installed flush with hard  surfaces. The microphone adopts side pressure equalization method, which increases the maximum sound pressure  level of the microphone by increasing the membrane tension.