Acoustic Calibrators

4226 Multifunction Acoustic Calibrator

4226 Multifunction Acoustic Calibrator

Multifunction Acoustic Calibrator Type 4226 enables simulated free-field calibration of microphones, sound level meters and other related instruments. Type 4226 generates accurate and stable sound pressure with a frequency varying from 31.5 Hz to 16 kHz in octave steps, plus a signal at 12.5 kHz.


  • Simulated free- and diffuse-field calibration of microphones
  • Verification of ½” and ¼” microphone setups and acoustic instruments conforming to IEC 60651 and ANSI S 1.4-1983
  • Verification of instruments according to parts of IEC 61672

Using the coupler provided, the test signal can be applied to either ½-inch or ¼-inch microphones, or picked up from an electrical output. For ease of use, Type 4226 can also apply a very accurate inverse A-weighting correction.

An external generator can be connected to Type 4226 if a frequency sweep or semi-automatic test is desired.