Composer l’espace is a spatialised work-concert for a moving flautist and clarinettist, conceived as an immersion in the resonant architecture of the Maison du Peuple in Brussels. Rather than serving as a setting for the performance, the building becomes a compositional parameter: its balconies, corridors, glazed passages, stage and audience area form a succession of acoustic zones through which a musical cartography gradually unfolds.

At the centre of the work is souffle — breath and air understood as a continuous material connecting performer, instrument and space. Flute and clarinet were chosen in part for their finely controllable directionality: air sounds, multiphonics, beats, white noise, granular textures and whistling can be projected, redirected and transformed through changes of orientation, distance and movement. Static and mobile passages, as well as written, memorised and more spontaneous actions, continually renew the relation between gesture and resonance.

The performers begin high above the audience on the imposing balconies, where height, separation and multidirectionality expose the building’s long resonances. Their gradual descent leads through corridors and partially enclosed glazed spaces, where sound becomes filtered and subtly muffled, before reaching the stage and eventually the audience itself. The performers thus operate as moving sound sources: the breath emerging from mouthpiece, embouchure, keys and bell changes not only through instrumental action but through the path it takes across the architecture.

Space itself becomes a form of acoustic amplification and transformation. Resonance, reflection, visibility and listening position continually reshape the same materials, approaching at times the thresholds between air and sound, presence and disappearance, the visible and the invisible. As sound travels from the edge of perception into the audience, the Maison du Peuple ceases to contain the work and becomes an active, evolving instrument within it.