Ever wanted to sing in a world-class concert hall without the years of training? Chœur d'un jour invites absolutely anyone to join a one-off choir: no auditions, no sheet music to prepare, just show up and lend your voice. The repertoire stays a surprise until you arrive, tied to whatever is playing at the Philharmonie that season. A playful vocal warm-up breaks the ice, then you learn your part and cap it off with a small performance. Pure, low-pressure joy.