Comparison of methods to determine corrections to obtain the free-field response of a sound level meter
Periodic verification of Sound Level Meters (SLM) includes a frequency response measurement by pressure calibration. Corrections must be applied to obtain the free field response, for which goals and tolerances are specified. Different methods may be used for the determination of the corrections, and this is the subject of a standard under development in IEC T29 WG17. The project aims at supporting the development of this standard by comparing different methods, in order to evaluate the reproducibility of the measurements and the uncertainties. A SLM modified for simplifying the measurement will be circulated among the participants, that use different methods for the determinations of the corrections. Results and associated uncertainties will be given by each participants, and the data will be analysed. A verified evaluation of the uncertainty of the measurement is the main output of the project.
Final Report 2011-04-06
The project has been completed and the report can be downloaded here>>