Achorripsis: a Sonification of Probability Distributions

The 1957 musical composition Achorripsis by Iannis Xenakis was composed using four different probability distributions, applied over three different organizational domains, during the course of the 7 minute piece. While Xenakis did not have sonification in mind, his artistic choices in rendering mathematical formulations into musical events (time, space, timbre, glissando speed) provide useful contributions to the “mapping problem” in three significant ways: 1. He pushes the limit of loading the ear with multiple formulations simultaneously. 2. His mapping of “velocity” to string glissando speed provides a useful method of working with a vector quantity with magnitude and direction. 3. His artistic renderings, ie. “musifications” of these distributions, invite the question, in general, as to whether musical/artistic sonifications are more intelligible to the human ear than sonifications prepared without any musical “filtering” or constraints (e.g. that they could be notated and performed by musicians).