Scheduling and composing with Risset eternal accelerando rhythms
Dan Stowell · University of Michigan Library Repository · 2011
Jean-Claude Risset described an "eternal accelerando" illusion, related to Shepard tones, in which a rhythm can be constructed to give the perception of continuous acceleration.The effect can in principle be derived from any rhythmic template, producing patterns with aspects of fractal self-similarity.Any attempt to use it compositionally must address the difficult issue of scheduling events (notes, beats) and structural changes in a way that integrates with the multi-layered self-similar rhythmic structure.In this paper we develop an approach to scheduling rhythms, melodies and structural changes over a Risset accelerando (or decelerando) framework.We derive the mappings which allow note sequences and sample playback to be incorporated.We discuss some compositional choices available within this framework, and demonstrate them via audio examples.