Calibration of sound intensity instruments
Sound intensity is a measure of flow of sound energy and is measured in dB relative 1 pW/m². Characteristics and requirements of the equipment for measurement of sound intensity are given in the standard IEC 61043. There are requirements both on the complete system and on the individual parts; microphone probe, analyzer and calibrator.
Equipment for measurement of sound intensity is verified by SP against the requirements in IEC 61043. Normally, microphone probe and analyzer are verified together but we can also verify each part separately.
The sound intensity calibrator is calibrated regarding:
- Sound pressure level
- Sound intensity level
- Frequency
- Distortion
- Residual intensity of noise source
Occurring defects
- One of the microphones has a small damage, it is still in working order but the microphone pair is no longer matched. This will result in a residual intensity level.
- As the probe is handled manually to a great extent, the ends of the cable are exposed to wearing which can result in poor contact.