Manuel Poletti – “On Air”: Working with Tomás Saraceno

For the past few months, the computer music designer Manuel Poletti has been working with the artist  Tomás Saraceno to prepare his large exhibition at the Palais de Tokyo.

What, in your experience, are the major differences between a collaboration in the domains of music and visual arts?

Generally, the practices of IRCAM, and more generally, the practices that are used in the milieu of live performances and those used in the visual arts are polar opposites. These two cultures either don’t know each other, or know each other poorly. However, what struck me when I started to work on the project was the desire to understand each other is very present. This is particularly true of the teams at the Palais de Tokyo who immediately understood the significance of our work and accompanied us throughout the project.

Our first mission was to magnify everything that had to do with sound in the exhibition, both in terms of its implementation (mainly spatialization) and of its contents.

What exactly is the role of sound in Tomás Saraceno’s oeuvre?

He likes sound. While it’s an integral part of his creations, we can’t really call him a sound artist: he is an artist who uses sound. Most of the time, he includes and/or creates sonification of scientific data—notably data from cosmic elements (movement of the planets, etc.). Our role in this production is to make suggestions in terms of the structure and material for sound diffusion—without going as far as composing—in order to augment the sonic aspect that is already developing in his work. So, I suggested some simple models of composition. For example, I showed them how much a combination of sounds, no matter what they are (and even sonification of scientific data), improves when spectrally structured from low to high. By providing a spectral topology (that can correspond to elements in a rock band, for example: bass, drums, rhythm guitar, keyboard, lead singer, and background singers) to sounds used in a sonic installation, we can organize it simply and effectively. After that, the choice of nature of these sounds and their evolution belongs to the artist. 

One of the central issues in this exhibit is, naturally, the sound diffusion and the spatialization; issues that are complicated even more by the rather unsuitable acoustics of the Palais de Tokyo. 

Unsuitable to say the least! The Palais de Tokyo is an open, raw space. So, its acoustics are also, naturally, “open and raw”. The idea is to create an acoustic space incorporated in the architectural space.

In general, each important piece in this exhibit has a sonic aspect. This isn’t an innovation: it’s fairly common in contemporary visual arts. However, spatialization, creating a homogenous sonic space like we know how, is a value added for the Palais de Tokyo.

For this, we took several acoustic measurements: we send out test sounds and capture their acoustic reverb that is analyzed in order to calibrate the system (equalization, delays, etc.). When everything’s set up, we can treat these new “spaces within spaces” like virtual rooms using the spatialization tools we usually use in concerts (notably Spatialisateur).

Other than this work on spatialization, you worked more particularly on three works: Webs of At-ten(t)sion, Sounding the Air, and Particular Matter(s).

We explored several ideas with Tomás Saraceno and his team for each of them. Webs of At-ten(t)sion is presented like a constellation made up of thousands of threads, like an impressionist painting that has been woven, stretched across the large rotunda in the Palais de Tokyo. The strings are still “sonorous”, meaning that, des despite their “raw” nature (we’re not talking about piano strings!), the must produce a sound that is amplified, processed, and diffused; like a giant harp that the visitors can walk inside and play.

Webs of At-tent(s)ion. Tryout at Studio Tomas Saraceno © Photography by Studio Tomás Saraceno, 201

One of the avenues of reflection was about the localization of the sound source where the visitor is playing. In keeping with Tomás’ wishes, which were that the visitors play in a “jam session”, I also suggested a few different scenarios that created an environment conducive to interactions—a little like a game. For this, I used simple concepts like that of a smooth tempo becoming, little by little, rhythmic. Or a tempo with an irregular rhythm evolving into a pulse, offering visitors an open score, adaptive in real-time, both in terms of evolutions and possibilities, according to the number of visitors or the frequency of their actions. These different scenarios lead to saturation, to an impoverishment, or to an explosion of the sound material…

For Particular Matter(s), the work was focused on its qualities and spatialization, not on the sound contents. The piece is presented as a screen that shows a real-time video feed of the dust motes floating in the air; their movements are detected and sonified.  While this sonification is happening (via a synthesizer Tomás’ team had already developed for the creation of the work), we decided to reproduce the trajectories of the dust motes using spatialization with a ceiling of loudspeakers to reinforce the connection between the visual and sonic aspects of the work.

Sounding the Air is a beautiful work to see: five strings made of spider silk  (Tomás works a lot with spiders) hung on a metallic structure five or six meters wide. Like the strings of a large aerial harp, these strings sway with the air and thermal changes that modify the room’s atmosphere. Again, Tomás’ team developed technology to follow the movements of the five strings to sonify them. The resulting sounds are sometimes pretty noisy, so I suggested sound design. Remaining faithful to Tomás’ imagination that—beyond the spiders—looks to the cosmos I imagined a cosmic aerial harp; I mean that it behaves as if it reacts to cosmic winds. The sounds extracted from the motion capture of the strings passes through resonating filters created using the sounds of a planet’s orbit (sonified to a classical vibrating strings harmonic spectrum) like a little solar system turning in space above the structure. Following the spider string’s movements makes it possible to slightly alter the pitch and volume of the resonating filters, like when a string is pulled and then relaxes, remaining connected to the physical strings in the installation.

Interview by Jérémie Szpirglas, journalist and author