CHARACTERIZATION OF THE TIMBER OF COMPLEX SOUNDS .2. ACOUSTIC ANALYSIS AND PSYCHOPHYSICAL QUANTIFICATION

A timbre space represents the mental organization of sound events at e qual pitch, loudness, and duration. The geometric distance between two timbres corresponds to their degree of perceived dissimilarity. The d imensions of such a three-dimensional space, established by Krumhansl [1] for a set of 21 synthesized sounds, were investigated with respect to their acoustic characteristics. Several acoustical parameters base d on the temporal and frequency properties of the sounds were calculat ed. The high degree of correlation of several parameters with the perc eptual axes lend support to previous interpretations of the qualitativ e character of two perceptual dimensions and their semantic attributes . The perceptual dimensions ''brightness'' and ''rapidity of attack,'' turn out to be quantitatively explainable by the center of gravity of the sound spectrum (CGS) and the rise time on a logarithmic scale (LT M), respectively. The third dimension, initially called ''spectral flu x'' corresponds partially to the standard deviation of the time-averag ed harmonic amplitudes from a spectral envelope (IRR). A new verbal de scritor, ''spectral fine structure'' seems to fit better with the resu lts of acoustic analyses.