Acoustic Calibrator Operating and Maintenance Guide
Acoustic calibrators produce a precise sound pressure level at one or more frequencies for calibrating sound level meters and measurement microphones.
I. Operating Procedures
- Preparation: Check the calibrator battery level before use. Inspect the cavity and O-ring for damage or debris.
- Coupling: Insert the sound level meter microphone fully into the calibrator cavity. Ensure a tight seal for accurate sound pressure level generation.
- Activation: Turn on the calibrator and allow it to stabilize for the specified warmup period, typically five to ten seconds.
- Calibration: Adjust the sound level meter reading to match the calibrator output level. Note any correction for microphone type or atmospheric pressure conditions.
- Verification: After calibration, remove the calibrator and verify the meter reading returns to ambient noise level.
II. Accuracy Considerations
- Acoustic calibrator output is affected by atmospheric pressure. Use barometric pressure correction when high accuracy is required.
- Verify that the calibrator cavity fits the microphone diameter correctly
- Allow the calibrator and microphone to acclimate to ambient temperature before calibration
III. Maintenance
- Keep the calibrator cavity clean and free of debris
- Replace batteries before the low battery indicator appears
- Check and replace the cavity O-ring if worn or damaged
- Send for calibration to an accredited laboratory annually
- Store in a protective case in a clean, dry environment
