Uncertainty in sound diffusion and scattering coefficients measurement
AGH University of Science and Technology
Monday 1 june, 2015, 15:00 - 15:20
0.9 Athens (118)
Sound diffusers are characterized by two main parameters, that describe the quality of the sound reflected from them. In the case of sound scattering coefficient, which is measured in reverberation chamber according to ISO 17497-1 standard, it is recommend to calculate the uncertainty according to the law of propagation. Only type A evaluation basing on measurement results is presented, assuming, that input values are independent, hence it omits the estimated covariance calculation. In the paper the method proposed by the standard is compared with values obtained taking into account correlation between input values and the results of the Monte Carlo method. It was shown that for some frequencies, the ISO standard uncertainty is much smaller, than calculated using other methods. Authors analyzed also factors affecting uncertainty in measurement diffusion coefficient, taking into account geometry of the measurement stand. Comparing the influence of the position changes of the sample obtained for different diffusers, uncertainty of the method was calculated depending on selected parameters.
ICS file for iCal / Outlook