Timbre saliency vs. timbre dissimilarity – What is the relationship?

Abstract

We have proposed the notion of timbre saliency as the attention-capturing quality of timbre. The definition of saliency requires an object to stand out with respect to its surroundings, implying dissimilarity between the object and its neighbors. What then might be the relationship between timbre saliency and timbre dissimilarity? A classic timbre dissimilarity experiment and a timbre saliency experiment were carried out with 20 participants on the same set of stimuli. Multidimensional scaling revealed a two-dimensional dissimilarity space. Using the features obtained from the Timbre Toolbox [Peeters et al., J. Acoust. Soc. Am. 130, 2902–2916 (2011)], the first dimension shows a high correlation with spectral centroid [r(13) = 0.845, p < 0.0001] and spectral spread [r(13) = 0.855, p < 0.0001], both based on the ERB-FFT model spectrum, and the second with the attack time [r(13) = -0.692, p = 0.004] and power spectral crest [r(13) = 0.732, p < .005]. This confirms spectral centroid and attack time as two major acoustic correlates of timbre dissimilarity. The saliency dimension shows a moderate correlation with the second dimension [r(13) = 0.578, p = 0.0241] but not with the first dimension [r(13) = 0.182, p = 0.517], suggesting that the saliency might be more related to the temporal characteristics of timbre.