arrow_back_ios

Main Menu

arrow_back_ios

Main Menu

arrow_back_ios

Main Menu

TYPE 4940

1/2" FREE-FIELD MICROPHONE, PREPOLARIZED

Free-field microphone for outdoor and industrial environment measurements and frequency analysis measurements from 2 Hz to 20 kHz.

  • Dyn. range : 14.6 – 146 dB
  • Freq. range : 6.3 – 20000 Hz
  • Polarization : Prepolarized
  • Sensitivity : 50 mV/Pa
  • Standards : IEC 60651 TYPE 1
img

TYPE 4940

expand_more
chevron_left
chevron_right

Prepolarized Free-field ½-inch Microphone Type 4940 offers significant benefits when used with portable instruments. It is particularly suitable for both outdoor and industrial environment measurements. It is also suitable for IEC 60651 Type 1 measurements and frequency analysis measurements.

 

USE SCENARIOS

  • Sound level meters  
  • Noise measurements according to IEC and ANSI standards
  • Transport noise measurements

 

FEATURES

  • Wide dynamic range from 14.6 dB(A) – 146 dB (3% distortion limit)
  • Low ambient temperature coefficient
  • IEC 60651 Type 1 approved with Modular Precision Sound Level Meter Type 2231

 

ROBUSTNESS

The microphone is capable of withstanding the IEC 68 232 1 metre drop test.

 

CALIBRATION OF SENSITIVITY AND FREQUENCY RESPONDS

The sensitivity can be calibrated at 250 Hz using Pistonphone Type 4228 with ½-inch Adaptor DP 0776. The actuator response can be measured using Actuator UA 0033. The free-field response can be obtained by adding the type-specific, free-field corrections to the actuator response.

  • Robustness: The microphone is capable of withstanding the IEC 68232 1 metre drop test.
  • Ageing and Assembly: Ageing at high temperature and the assembly of the microphone in a clean room environment ensure that the microphone can be used in high humidity environments and still produce reliable results.
  • Microphone Data Disk: The microphone is supplied with 3½-inch microphone data disk. The disk includes all calibration data as well as free-field, random-incidence and pressure-field corrections. The influences of different accessories are also included.
  • Calibration of Sensitivity and Frequency Response: The sensitivity can be calibrated at 250 Hz using Pistonphone Type 4228 with ½-inch Adaptor DP 0776. The actuator response can be measured using Actuator UA 0033. The free-field response can be obtained by adding the type-specific, free-field corrections to the actuator response
TYPE 4940
Standard IEC 61094
Sound field Free field
Polarization voltage 0V
Sensitivity 50 mV/Pa
Lower limiting frequency 6.3 Hz
Higher limiting frequency 20 kHz
Inherent noise 14.6 dB(A)
Upper limiting of dynamic range 146 dB
Diameter 1/2 inch
Venting Rear
Minimum Temperature -30 °C
Maximum Temperature 150 °C
Minimum Temperature -22 °F
Maximum Temperature 302 °F