Perceptual analysis of synthesized struck bars

Abstract

This study is part of a project seeking to understand musical timbre and perceptual phenomena of the sound environment. It concerns the sensitivity of listeners to sounds emitted by simple vibrating structures, such as xylophone bars. Previous studies of timbre have characterized this attribute in terms of a small number of perceptual dimensions of an analytic nature (attack time, spectral centroid, spectral flux). Other studies have suggested a return to the physical characteristics of the sound sources themselves in order to understand their influence on timbre perception. Sounds were synthesized with a computer model of the vibrating bar developed at ENST that allows precise control of physical parameters. Listeners made dissimilarity judgments on all pairs of different sounds. Multidimensional scaling analyses of these data yield a perceptual space with dimensions that correspond strongly to the varied physical parameters (material density and the first term of internal damping) as well as to salient auditory dimensions (pitch for the former and a combination of spectral centroid and decay rate for the latter). These results argue in favor of a privileged processing of source characteristics by the auditory system.