Calibration level:Max. level: 140 dB (re. 20 μPa)Usable frequency ranges (preamp. and mic. dependent):Range: 0.27 Hz (– 3 dB) to 100 Hz to 1.1 Hz (– 3 dB) to 100 Hz
The G.R.A.S. 42AE Low-Frequency Calibrator permits microphone calibration at frequencies down to 0.01 Hz for both front and rear-vented microphones. It produces a constant sound pressure level down to very low frequencies.