Desain, P., & Honing, H. (1996). Modeling Continuous Aspects of Music Performance: Vibrato and Portamento. In B. Pennycook, & E. Costa-Giomi (eds.), Proceedings of the International Music Perception and Cognition Conference. CD-ROM. Montreal.


Research in the psychology of music dealing with expression is often concerned with the discrete aspects of music performance, and mainly concentrates on the study of piano music (partly because of the ease with which piano music can be reduced to discrete note events). However, on other instruments, what happens during and in-between notes can be even more relevant then the realization of the note onsets and offsets, an issue not often addressed in music psychology. A noteworthy exception is the work of Seashore (1938) who pointed out the importance of continuous aspects in music performance. It is remarkable that, since these early exploratory studies, this field received little attention. A reason for this could be the relative inaccessibility for psychologists and musicologists of the data processing techniques needed. Another reason could be the sheer amount of information present in these modulation signals. Compared to discrete data there are many more degrees of freedom to explain. And finally, direct experimentation without a model is not likely to give results that go beyond the exploratory studies of Seashore and his colleagues. However, while the availability of current signal processing techniques makes the modulation signals (of e.g. pitch or dynamics) easier to extract, their shape is still quite complex. It is difficult to analyze and model them directly. In this presentation we describe an approach in which measured modulation signals (of pitch and amplitude) are modeled by a composition of idealized components using an analysis-by-synthesis method. This proposed decomposition can be formalized and verified using the notion of generalized time functions that was developed for the construction of control functions for sound synthesis (Desain & Honing, 1992; 1995). These functions describe abstract temporal behavior. Once modeled, the continuous behavior for each note and each transition can be expressed again as a discrete set of parameters, whose evolution over a series of notes can be linked to structural descriptions of the music. In this way we can adapt the methods developed specifically for discrete expressive attributes to the study of continuous aspects of musical expression.

Full transcript of the ICMPC 1996 Keynote address, with sound examples and animations.