Type 4144 is a 1-inch pressure-field microphone, that is, a microphone where the damping of the diaphragm is such that the pressure frequency response is flat over a wide frequency range. Hence no correction is needed to the pressure response below 8 kHz. The use of pressure-field microphones is recommended where measurement of the local pressure is of interest, for instance for coupler measurements or measurements at walls or surfaces. The excellent stability of Type 4144 combined with its low inherent noise and high sensitivity makes it the perfect choice for coupler measurements and other laboratory type measurements.