Musique sur l'eau composed by Christopher Ducasse, sung by the festival choir at the first-ever TrebleFest Ottawa | Upper Voices Choir Festival, April 27, 2025; Dr. Hilary Apfelstadt, Guest Director.

Festival Choir includes individual singers from across Ottawa, as well as TrebleFest participating choirs: Aella Choir, Cantiamo Girls and Women, OCC Chamber Choir, and the host choir, Hypatia's Voice.