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.