Microphone Cartridges

4943 1/2-Inch Diffuse-Field Microphone

4943 1/2-Inch Diffuse-Field Microphone


  • Diffuse-field measurements
  • In-car measurement
  • High humidity environments


A diffuse-field microphone, also called a random-incidence microphone, is designed to have a uniform response when signals arrive simultaneously from all angles. They should therefore not only be used for measurement in reverberation chambers, but in all situations where the sound field is diffuse, or where several sources are contributing to the sound pressure at the measurement position. Practical examples are indoor situations, where the sound is reflected by walls, ceilings, and objects in the room, or measurements inside a car.


The microphone is capable of withstanding the IEC 68-2-32 1 metre drop test.


The sensitivity can be calibrated at 250 Hz by using Pistonphone Type 4228 with ½” Adaptor DP 0776, or at 1 kHz using Sound Level Calibrator Type 4231. For calibration at other frequencies use Multifunction Acoustic Calibrator Type 4226. The actuator response can be measured using Actuator UA 0033. The random-incidence response can be obtained by adding the type-specific, random-incidence correction to the actuator response.


Capacitance: 20 pF
Diameter: 1/2
Dynamic range: 15.5 – 148 dB
Frequency range: 3.15 – 10000 Hz
Inherent noise: 15.5 dB A
Lower limiting frequency -3dB: 2 Hz
Optimised: Diffuse Field
Polarization: Ext polarized
Polarization voltages: 200 V
Pressure coefficient: -0.008 dB/kPa
Sensitivity: 50 mV/Pa
Temperature coefficient: -0.015 db/ºC
Temperature range: -40 – 150 C
Venting: Rear
Weight: gram
Sound field: Diffuse-field
Microphone type: Diffuse Field