Keynote presentation on the Algorithmic Arts, in the context of the Meta-Xenakis transcontinental celebration, at the Music Library of Greece, in May 2022, entitled “Iannis Xenakis and Algorithmic Music”.

Xenakis was a pioneer in algorithmic composition of music and art. He combined architecture, mathematics, music, and performance art to create Avant-garde compositions and performances that could not have been possible without his deep understanding of algorithms, mathematics, and his use of controlled randomness, i.e., stochastic processes. This talk will sample some of Xenakis’ works in algorithmic and stochastic music, such as Concrete PH, Metastasis, and UPIC, and explore the types of music that Xenakis would be writing today having access to today’s modern technology of smartphones and computing devices.

This talk-performance – in the intersection of science and art – will introduce some of Xenakis’ techniques to a general audience, and explore how the field of stochastic music has advanced in the twenty years since Xenakis’ passing.  While ideas and techniques pioneered and used by Xenakis are now well understood, today’s music technology has evolved through integration of artificial intelligence, advanced algorithms, and human-computer interaction – techniques and technology that were unavailable to Xenakis.

The talk will also provide an overview of the recent two-day workshop on the Algorithmic Arts (http://AlgoArts.org), inspired in part by Xenakis, and cosponsored by the National Science Foundation (NSF) and the National Endowment for the Arts (NEA), in the United States.

The talk (in English) is available in its entirety here.

This piece explores how stochastic and aleatoric techniques introduced by Iannis Xenakis can be combined with classical music theory, modern mathematics / fractal geometry, and modern technology / smartphones. It was presented in the context of the Meta-Xenakis transcontinental celebration, at the Music Library of Greece, in May 2022.

“on the Fractal Nature of Being…” is constructed using a harmonic theme interwoven into a fractal. Audience members participate with their smartphones, using their speakers and accelerometers to control aspects of the performance. The harmonic theme is first introduced, and then repeated by different instruments (with Yiannis Bafaloukas on piano, Daniel Brown on cello, and Devon Wyland on bassoon), at different levels of granularity – creating space for the fractal to unfold. A probability density function controls the interplay between consonance and dissonance – this is a meta-Xenakian idea, as Xenakis mainly focused on the probabilities between sounds and silence.

“Éolienne PH” (also known as “Be the Wind”) is a piece created for the 2022 Meta-Xenakis celebration, utilizing audience smartphones for its performance. It was inspired by Iannis Xenakis’ “Concret PH” (see further below). This recording was captured at International Symposium on Electronic Art (ISEA 2022) in Barcelona, in June 2022.

The piece uses recordings of sounds found in Nature, including that of flowing water and bird song – to create a restorative, meditative experience. Similarly to its counterpart, sounds are partitioned into small fragments, and then pitch-shifted and overlaid, to create a granular, ever-unfolding sound texture.

Éolienne PH utilizes audience smartphones to deliver its sounds. Participants are asked to move freely around, thus generating independent, aleatoric trajectories for sounds. This creates infinite possibilities for sound texture and placement. Participants may also produce high-quality, binaural wind-chime sounds, by tapping on their smartphone screens. This makes them active contributors to the unfolding soundscape, and invites (but does not require) deep listening, and possibly collaboration.

This is a recreation of Iannis Xenakis’s avant-garde piece, “Concret PH” (1958), utilizing audience smartphones. Xenakis was a pioneer in algorithmic composition of music and art. He created this piece for the Philips Pavilion at the 1958 World’s Fair. He used a recording of burning charcoal, partitioned into one-second fragments, and then pitch-shifted and overlaid, to create a granular, unfolding sound texture. It lasts 2 and 1/2 minutes.

Our retelling uses background from the original, and a hammer-on-anvil sound to recreate individual charcoal sounds. It also uses a probability density function to control the unfolding of sounds, so that the sonic outcome remains the same, regardless of how many smartphones are present. This recording was captured on a high-quality 3D binaural microphone, at the University of Maryland, College Park, USA, in April 2022. Participants were asked to move freely around, resembling people moving inside the Philips Pavilion in 1958.