Microphone Cartridges

4966 1/2-Inch Free Field Microphone

4966 1/2-Inch Free Field Microphone

Type 4966 is a robust and stable free‐field microphone cartridge designed for high‐precision acoustic measurements. It is developed and refined for measurements where a high sensitivity microphone with a full 20 kHz bandwidth is preferred and is optimized for use with the protection grid in place.

Type 4966 is prepolarized, so it is well suited for use in batteryoperated equipment and environments with high humidity.


  • Precision sound‐measurements
  • General purpose sound‐measurements
  • Electroacoustic measurements

Being prepolarized, Type 4966 can be used with both CCLD* and classical Brüel & Kjær preamplifiers.


Capacitance: 14 pF
Diameter: ½”
Dynamic range: 14.6 – 144 dB
Frequency range: 5 – 20000 Hz
Inherent noise: 14.6 dB A
Lower limiting frequency -3dB: 3 Hz
Optimised: Free field
Polarization: Prepolarized
Polarization voltages: 0 V
Pressure coefficient: -0.01 dB/kPa
Sensitivity: 50 mV/Pa
Temperature coefficient: 0.003 db/ºC
Temperature range: -30 – 150 C
Venting: Rear
Weight: gram
Sound field: Free-field
Input type: CCLD IEPE
Microphone type: Free field