Iannis Xenakis in his studio, Paris, c. early 1960s. Photographer: Adelmann – Collection: Françoise Xenakis Xenakis: Arts / Science Proceedings / Actes Friday, October 1, 2010 Vendredi 1er octobre, 2010 Schulich School of Music, École de musique Schulich, McGill University McGill University Edited by / Édité par Fabrice Marandola McGill University - CIRMMT C I R Centre for Interdisciplinary Research M M T in Music Media and Technology Published by / Publié par: McGill University, CIRMMT ISBN: 978-0-7717-0699-8 All copyrights remain with the authors / Tous les actes du colloque demeurent la propriété de leurs auteurs. Proceedings may be found online at / Les actes peuvent être téléchargés à l’adresse: http://www.cirmmt.mcgill.ca/activities/Xenakis-conference Scientific committee / Comité scientifique Sean Ferguson McGill University - CIRMMT James Harley University of Guelph Sharon Kanach Centre Iannis Xenakis, Xenakis Project for the Americas Jean Lesage McGill University Fabrice Marandola McGill University - CIRMMT Jon Wild McGill University - CIRMMT The CIRMMT team / L’équipe du CIRMMT Sean Ferguson Director / Directeur Fabrice Marandola Associate Director - Artistic Research / Directeur associé - recherche artistique Gary Scavone Associate Director - Scientific and Technological Research / Directeur associé - recherche scientifique et technique Jacqueline Bednar Events & Administrative Coordinator / Coordinatrice évenementielle et administrative Julien Boissinot Systems Manager / Responsable systèmes Sara Gomez Research Administrator / Administratice de recherche Harold Kilianski Technical Manager / Responsable technique Yves Méthot Electronics Coordinator / Coordinateur pour l’électronique http://www.cirmmt.mcgill.ca/ 2 Schedule / Programme 8:30 Registration / Inscription 9:00 Opening remarks / Remarques préliminaires 9:15 Session A: About Xenakis compositional principles / Des principes compositionnels de Xenakis Ronald Squibbs, Eliot Handelman, Jimmie Leblanc Chair / Modérateur: Sean Ferguson 10:45 Coffee break / Pause café 11:00 Session B: Performing Xenakis / Interpréter Xenakis Benjamin Duinker, John Klepko, Stéphanos Thomopoulos Chair / Modérateur: Fabrice Marandola 12:30 Lunch / Pause déjeuner 14:00 Keynote lecture / Conférence invitée (Sharon Kanach, Centre Iannis Xenakis, Xenakis Project for the Americas) Due to unforeseen circumstances, Philippe LerouX (Université de Montréal) is unable to deliver the Keynote lecture / Pour des raisons indépendantes de sa volonté, Philippe Leroux (Université de Montréal) ne pourra pas donner la conférence invitée 15:00 Session C: Architecture and technology / Architecture et Technologie Joseph Clarke, Alcides Lanza Chair / Modératrice: Sharon Kanach 16:00 Coffee break / Pause café 16:30 Session D: Analysing Xenakis music / Analyser la musique de Xenakis Robert Hasegawa, Benjamin Levy, James Harley Chair / Modérateur: Jon Wild 18:00 End of the conference / Fin de la conférence 3 Aspects of compositional realization in Xenakis’s pre-stochastic and early stochastic music Ronald Squibbs, PhD Associate Professor of Music Theory, University of Connecticut, Connecticut In the preface to the score of Metastaseis (1953-54), Xenakis indicates that certain of the work’s features prefigured aspects of stochastic composition, the approach that he would adopt in Pithoprakta (1955-56) and subsequent works. While there are good reasons to contrast the serial procedures that underlie certain passages in Metastaseis with the stochastic approach taken in later works, there are also significant points of contact between Xenakis’s compositional realizations of both approaches. This presentation compares a passage from the first middle section of Metastaseis with passages from Analogique A (1958-59) as well as with general features of other early stochastic works. Among the issues to be considered are the methods used for generating the events that appear on the musical surface, characteristics of the instrumentation, and rhythmic structure. In both the pre-stochastic and early stochastic music, the rhythm is frequently regulated by means of superimposed, non-coinciding divisions of the beat, producing a metrical grid system that Xenakis referred to as “differential durations.” The differential durations provide support both for the polyphonic combinations of structural voices in Metastaseis and for the continuous streams of sonic events produced in the process of stochastic composition. When the output of stochastic functions is filtered through the multi-layered grid produced by the system of differential durations, the individual instrumental parts produce a kind of virtual polyphony. Although the pitches move freely within the registral boundaries defined by the composer, the part writing features successions of arpeggiated triads, scale fragments, and other melodic motives commonly found in the music of early modernist composers. Thus, even as Xenakis’s music moved decisively into the future by distancing itself from techniques that had been developed by his predecessors—such as serialism or free motivic association—the musical surfaces in his early stochastic works still show stylistic affinities with the music composed according to older methods. In order to test whether it is possible to achieve these effects while adhering closely to the principles of stochastic music as defined by Xenakis, a short eXcerpt from Analogique A is compared with a hypothetical continuation based on the output of a stochastic compositional algorithm. The results of this eXercise in model composition indicate that the instrumental parts do indeed demonstrate the kinds of quasi-motivic patterns found in Xenakis’s early stochastic works. Further, it appears that the use of differential durations contributes significantly to the formation of these patterns, both by regulating the overall flow of sonic events and by segmenting the individual parts by means of intermittent rests. 4 The Xenakian outside-time as motion perception: an analysis and simulation Eliot Handelman, PhD Center for Music-Computational Thought, Montreal Iannis Xenakis proposed a psychologically relevant distinction between music as performed – which he called "inside-time" – and music as heard or felt, which he called "outside-time." In one interpretation, the apprehension of music is characterized by the fact that parts of the music can be voluntarily remembered, i.e., not bound by the order given in performance. Xenakis (4) presented this diachronic listening model in a "tentative axiomatization", roughly asserting that: • Musical events can be grouped together forming segments. • Some segments are remembered as "landmarks". • Landmarks can be compared with past landmarks. The difference between landmarks can be considered as a "step", "displacement" or "jump" from one point to another in a composition. Xenakis made a further point which spoke of "linking" such steps together in a chain in one of two orientations, described as "accumulation or de-accumulation". He did not eXplain what he meant by these terms but we propose a new clarification based on three ideas. 1. What Xenakis calls "segment" or "landmark" we call "shape", an auditory analogy to the visual shape, which played a vital role in Xenakis' thinking. But there is a suggestion in the neuroscience literature (1) that the cortical processing machinery for both is homologous. Psychological parallels are manifest. As with visual shape, auditory shape can roughly be taxonomized in terms of simplicity: there are simplest auditory shapes, such as an even glissando. We argue that the simplest shapes are the perceptually most salient, and constitute a basic category of the "landmark." Hence the visuality of Xenakis' thought seems to lead back to the auditory (3). 2. The "perceptual step" is, roughly, a change in degree, or size, of a shape. The "step" from one loud and furious passage to another is the felt increase or decrease in loudness or furiousness (or whatever the defining features may be). In the Xenakian landmark step chain, shapes increase and decrease in size. There are clearly simplest ways to do this. 3. These changes result in the perception of motion, which we see as a low-level music perception substrate related to the listener's perception of motion in the physical world. (2) But how to construe the problem of motion in the criss-crossing of different landmark chains? We offer the concept of "motion asymmetries," the interlocking of chains with a view to imbalance or asymmetry, generating patterns of diachronic motion. Asymmetries of the landmark/shape-linking/chaining "outside-time" can be shown in an enormous amount of music – here, we will demonstrate the relevant ideas in folksong and in Xenakian compositions. As an appendiX to the talk, I will indicate how these questions can be eXplored not only as problems in descriptive computational music theory, but in a generative music composition system in which an "outside-time" perspective is fundamental. The success of this reveals that the Xenakian "outside-time" concept offers a powerful theoretical perspective on musical perception and its relation to visuality, the organization of music, and on generative composition. 5 References (1) Belin P., Fecteau S. & Bédard C. (2004) Thinking the voice: neural correlates of voice perception, Trends in Cognitive Sciences 8 (2) Nussbaum, C. (2007) The Musical Representation: Meaning, Ontology, and Emotion. MIT Press. (3) Schaub, S. (2005) Akrata, For 16 Winds by Iannis Xenakis: