Karl erich schumann’s principles of timbre as a helpful tool in stream segregation research

Abstract

The following text deals with timbre-dependent stream segregation. Combining the ideas of Gestalt principles, auditory scene analysis and Schumann's principles of timbre, the following hypotheses are proposed and examined: (i) Alternating timbres with matching formant positions are perceived for the most part as one sole melodic stream. (ii) Alternating timbres with non-matching formant positions are perceived for the most part as two interwoven melodic streams. (iii) Alternating timbres which have on the one hand formants and on the other hand fluctuations as primary attributes are perceived for the most part as two interwoven melodic streams. (iv) Alternating timbres of which the main attributes are fluctuations are perceived for the most part as one sole melodic stream. In this experiment based on Wessel (1985), hypotheses 2 and 3 were fully confirmed, whereas hypotheses 1 and 4 could not be fully confirmed. Possible causes for this are discussed: the invariable melodic contour of the stimuli as well as the tempo in which they were played; furthermore, the mental situation of the subjects at the time of the experiment.