England's GaryClark and David Carter both shot opening rounds of 69 to lie three shots off the lead in a group containing South African Trevor Immelman.
Heart, Randy Newman, Public Enemy and Rush are expected to perform at Thursday's star-studded event, while Usher will sing for Jones, Carole King will perform for Adler and John Mayer and GaryClark Jr. will pay tribute to the late King.
Keb' Mo' and Taj Mahal paid tribute to the blues in their acoustic set, while newcomer GaryClark Jr. had the crowd on its feet throughout most of his electrifying set, which was followed by another fiery set, this one by Jeff Beck.