Timbre of complex tone bursts with time varying spectral envelope

Temporal change of a spectral envelope is one of five major acoustic parameters which are considered to determine the timbre of a time-varying sound.[Schouten(1)]. An experiment was conducted to see the effects of rapid time-varying spectral envelopes on the timbre of short-complex tone bursts ranging from 60 ms to 100 ms. Each burst consists of three segments: an initial steady segment, a middle frequency-glide segment and a final steady segment. Similarity judgments of pairs of these stimuli were made. A non-metric two-dimensional analysis of the experimental data showed that the timbre of short-complex tone bursts with a frequency-glide segment where the spectral envelope is changed in time depends mainly on two factors. One corresponds to dynamic property which appears to be related to the temporal position of the glide segment. The other corresponds to pitch sensation.