There are scores of different groups and bands playing in Nyon over the next three days, all in different styles and genres providing live and free music for the town. There is a site dedicated to this festival so whether you prefer classical music down at the Conservatoire, or rock in the street or choral music in the “temple” of Nyon then check the site out for full timings and venues.
Also note there is also a classical concert on this Sunday (not part of the fete) at 17:00 in Nyon performed by Theodor Küng on Violin and Matt Bilyard on Piano at the Salle de la Colombiere in Nyon.