R​ê​ver l'imperceptible

Last spring, I was commissioned by Radio France to produce a radio musical work for a France Musique program (Création Mondiale hosted by Anne Montaron). There was a partnership with INA GRM, where I was invited to do a one-week residency in their studio to compose a 10-minute electroacoustic piece, in the form of 5 fragments of 2 minutes each. I chose to title my piece "Dreaming the Imperceptible", a partial nod to the American activist Starhawk's book "Dreaming the Obscure", whose title I took up a bit - but with a totally derivative intention. The initial constraint that I had set myself was to start with night sounds from my environment. Are night sounds different from day sounds?