Per Voce (For voice), 2025, is a commission by Lydia Ourahmane made in collaboration with her sister Sarah Ourahmane, a composer and musician. A composition written for three visually impaired singers unfolds across two rooms of the museum. Barely visible but perceptible to the touch, the score is embedded into the walls of each room to remain permanently open to future activations.

The score studies the architecture: it is completely determined by the room’s dimensions, with windows and doors dictating pauses and wall lengths determining duration. Upon activation, each singer navigates their part, tracing the score in Braille along the walls as they move through the Castello.

When translating a musical phrase into Braille, the six-dot cell represents the pitch and rhythm of each note alongside which key and octave the composition is written in. The scores manifest as a single line with the notes, their duration, height in octaves, ligatures, pauses and interpretative instructions communicated one after the other in sequence.

By reducing the amount of ornaments or instructions each singer apports their personal logic to each phrase. The singers must therefore memorise the distinct elements and then piece them back together, creating an amplified possibility for entropy, evolving with each singer’s method determining the spatial choreography of the score.

Room 5 hosts a kinetic audio system on linear rails replaying a recording of the performance set onto three speakers. The speakers move to replicate each singer’s cadence, translating the score in their absence.