The Sound Level Calibrator is a sound source intended for quick and direct calibration of sound level meters and other sound measuring systems . It is designed to fit 1" and 1/2" and 1/8" microphones. The calibration frequency is 1 kHz. (the reference frequency for the standardized international weighting networks) , so the same calibration value is obtained for all weighting networks (A. B. C, D and Linear) .

A stabilized 1 kHz oscillator feeds a piezoelectric driver element which vibrates the diaphragm and creates the sound pressure level in the coupler volume . Sound level meter/ sound pressure level meter connected to the coupler receives the sound intensity and displays the reading in decible by direct measuring method.