Characterising Nonlinearities in Acoustic Transfer path Measurements

Mohamady, Samira and Montazeri, Allahyar (2019) Characterising Nonlinearities in Acoustic Transfer path Measurements. In: 23rd International Congress on Acoustics, 2019-09-09 - 2019-09-13, EUROGRESS.

Abstract

The purpose of this study is to characterize the measurement errors in impulse response measurement in room acoustic analysis. An auditor room is considered as a case study. A repeated measurement is carried out to measure 8 transfer function from a loudspeaker in the corner of the room and two microphone installed in the ear position. Here we use multi-sine excitation signal for measurement and compare the results with other type of excitation signals such as sweep sine signals. As the next step all 8 transfer functions are estimated with only one experiment using multichannel excitation and multi-sine signal. This will give not only a better signal to noise ratio but also reduce the experiment time as well as a more accurate transfer path in case of coupling between transfer functions. In this case, we are able to quantify various sources of uncertainties such as measurement noise, leakage, and nonlinear distortion by deeper analysis of the results. The approach relies on robust local polynomial method as an advanced technique for non-parametric measurement of the room impulse responses. The analysis shed light on the measurement technique and factor influencing to reduce the measurement errors and produce a high quality audio system.