Pressure gradient

A type of microphone construction which supports the transducer diaphragm on the top and bottom, leaving it open to the air on both sides. This produces a figure-eight pattern polar response. Mics of this type are more complex and delicate than pressure operation-type mics, and have many more mechanical and physical problems such as extreme susceptibility to handling noiserumble, sensitivity to wind, and proximity effect. In addition, the diaphragm assembly has to compensate for the inadequacies of the pressure gradient by making the diaphragm resonate at very low frequencies, generally restricting the smoothness and extension of the very lowest part of the audio spectrum. These disadvantages are, however, overlooked because of the directivity of these microphones. Cardioid microphones are a combination of pressure gradient and pressure operation transduction within a single unit.