Event:

This presentation aims at clarifying which signal parameters do and do not have an influence on musical timbre perception. Besides pitch, loudness and duration, musical timbre is one of the four defining properties of a musical sound. Timbre provides information on the kind of musical instrument playing the note, how the musician played it and the context within which the note was played. Therefore, understanding musical timbre perception corresponds to understanding how we make sense from musical sounds.

Unlike for pitch, loudness and duration, there is no generally accepted definition of musical timbre. Thus, it is not clear which signal parameters are salient to its perception. Previous research focuses on deriving musical timbre from the perceived similarities within musical sounds. Such approaches yield a considerable range of signal correlates that might contribute to musical timbre, but the findings depend on the stimuli used, and they are not coherent or generally extensible.

Musical timbre perception is considered as a source identification process targeted at the specific subclass of sinusoidal combinations that occur in the acoustic signals emitted by musical instruments. It is postulated that the auditory system at first splits the incoming sound into auditory sources, and only then, once it "knows" what a source is, draws information from it. In that sense, the decision on what constitutes a source limits the amount of information, or the timbre percept, that can be drawn from that source.

A series of listening tests, targeting the effects of static and dynamic signal properties as well as the effects of the temporal envelope on auditory source separation were conducted. The outcomes suggest that there are indeed signal parameters limiting auditory source perception and thus, musical timbre perception. Based on the findings, a conceptually and perceptually meaningful definition of musical timbre is derived, which is hoped to provide a valid starting point for further research on human and machine listening alike.