Calibration Pitfalls: Is Your 94dB Actually 94dB?
1. O-ring leakage
The calibrator must form a completely airtight seal to the microphone capsule.
If the O-ring or adapter leaks, the calibration level will read too low. Measurement software may then compensate incorrectly, resulting in logged SPL values that are higher than the actual sound pressure.
Recommendation:
Inspect calibrator adapters regularly. Replace O-rings showing cracks, wear, or loss of elasticity.
2. Background noise during calibration
Calibration performed in a noisy environment, such as during stage load-in, can be contaminated by ambient sound entering the calibrator.
Observe the RTA during calibration. A correct setup shows a single, narrow peak at 1 kHz and a low, clean noise floor.
If the noise floor appears uneven or “hairy” around the peak, relocate to a quieter space and repeat the calibration.
The principle
Calibrate at the start of every show day.
Changes in atmospheric pressure and temperature can alter microphone sensitivity enough to shift readings by 1–2 dB, which is significant for compliance and documentation.
Smaart is excellent on its own, but most users find they get much more out of it after some structured training. That’s where our seminars come in. At TZ Audio we run practical seminars, both online and in-venue. We offer seminar-only or full “all you need packages” including software & hardware. It’s simply the fastest way to become comfortable and confident with the measuring a sound system.
If you’re in Norway, Sweden, Denmark or Iceland – or elsewhere – we offer is online seminars and traveling to Norway is a valid option too of course. We’re here if you have any questions about the software or upcoming seminars.
Thanks for reading!