Timbre parameter representations of aircraft cabin sound quality

In order to describe the influences of noise timbre on aircraft cabin sound quality, three groups of subjective evaluation experiments were conducted, including dissimilarity evaluation, semantic differential, and preference comparison. Firstly, the results of dissimilarity evaluation indicated that the timbre of aircraft cabin noises could be described with a four-dimensional space. Secondly, the regression analysis revealed that the latter two dimensions were related to semantic scales, in which dimension 3 was interpreted as roaring and muffled, and dimension 4 was interpreted as harsh and rhythmic. Thirdly, four acoustic parameters (noisiness, ERB spectral kurtosis, short-time spectral skewness, and ERB spectral variation) were derived to obtain the quantitative interpretation of each dimension. Finally, by analyzing the relationship between the preference scores on the one hand and the four timbre parameters on the other hand, it was illustrated that a preferable sound should have almost no tones and was random, while its spectrum should possess a flat and symmetrical distribution.