Microphone Cartridges

4964 1/2-Inch Infrasound Microphone

4964 1/2-Inch Infrasound Microphone

Type 4964 is designed for high-precision, acoustic measurements where an infrasound microphone with high sensitivity is required. Being prepolarized, Type 4964 can be used with both CCLD and classical preamplifiers.


  • General noise measurements
  • Wind turbine measurements
  • Sonic boom measurements


Capacitance: 14 pF
Diameter: 0.52
Dynamic range: 14.6 – 146 dB
Frequency range: 0.02 – 20000 Hz
Inherent noise: dB A
Lower limiting frequency -3dB: 0.02 Hz
Optimised: Free field
Polarization: Prepolarized
Polarization voltages: 0 V
Pressure coefficient: -0.01 dB/kPa
Sensitivity: 50 mV/Pa
Temperature coefficient: -0.006 db/ºC
Temperature range: -30 – 150 C
Venting: Rear
Weight: gram
Sound field: Free-field
Input type: CCLD IEPE
Microphone type: Free field