Freedom and Constraints in Timing and Ornamentation (review)

Although the title as well as the subtitle of Renee Timmers's book, Freedom and Constraints in Timing and Ornamentation: Investigations of Music Performance, do not make it clear, this book is not the result of traditional studies on performance practice; rather, it is a collection of five empirical, computer-assisted studies of expressive temporal interpretation in music, specifically in piano performances. Hereby, "freedom" and "constraints" exist in both stylistic conventions of music and cognitive processes during the performance. The main thesis was to measure and analyze the onset timing and the expressive variations of tempo and timing of music performances by professional pianists, with a particular interest in the timing of melodies and of ornaments.

Ms. Timmers's book is actually a dissertation, written and defended in 2002 at the Catholic University of Nijmegen, The Netherlands, as part of the Music, Mind, Machine (MMM) project. The MMM project deals with computational modeling in music and its psychological validation and application. As such, the MMM project focuses currently on three main research areas: domain studies on rhythm perception, expression, and music and motor behavior; methodological studies regarding programming and music representation; and applications of the previous two research areas, such as the development of POCO, a workbench for research on expression in music (see the MMM Web site: www.nici.kun.nl/mmm/). The book being reviewed falls mainly into the first category (expression in music), although the methodologies include the use of the POCO workbench. The author, who was a member of the MMM project team, is currently a research fellow at the Austrian Research Institute for Artificial Intelligence in Vienna, working on the project "Computer-Based Music Research: Artificial Intelligence Models of Musical Expressions."

Although this book is a dissertation and Ms. Timmers is listed as the sole author on the book's cover, only one of the chapters (besides the initial Introduction and the concluding Discussion) was solely written by Ms. Timmers herself. The credits under each chapter header show that all other chapters were written by several scholars, and published in scholarly journals (Journal of New Music Research, Psychology of Music, and Music Perception). These coauthors are Rinus Aarts, Ric Ashley, Peter Desain, Hank Heijink, Henkjan Honing, and W. Luke Windsor.

The first study, "Issuing an Empirical Musicology of Performance," provides a methodological foundation of computer-assisted performance research, as it discusses different definitions of expressive timing and the methods to approach expressive timing. The second study, "The Influence of Musical Context on Tempo Rubato," focuses on tempo rubato as it relates to different structural contexts in music, and how different contexts can influence the performance of the same melody. To do so, three pianists were asked to perform excerpts of the melody of Variations on an Original Theme, op. 21, no. 1, by Johannes Brahms, whereby the melody was performed in different settings: without bar lines, with bar lines, with countermelody, counter-melody only, with block chords, and all material together. The results are fascinating in that they show that pianists change the onset timing of the melody depending on the musical contexts and structure. For example, "the addition of chords often caused a lengthening of the melody notes with chords, and the addition of a countermelody constrained the lengthening of a melodic ornament. The melody proved to be the primary expressive source, while chords and a countermelody were good second ones. Both the variety in timing patterns and the extent of tempo rubato appeared to increase with increasingly complex conditions" (p. 43).

The third study (the only one written solely by Ms. Timmers), "On the Appropriateness of Performance Rules," shows that musical interpretation, with regard to its expression, depends on its relation to initial expressive variations. Thus, the freedom and constraints of performance are set by the...