premise: Brad Wilk started his career as a singer.
hypothesis: Audioslave . The four-piece band consisted of Soundgarden lead singer/rhythm guitarist Chris Cornell , and Rage Against the Machine members Tom Morello ( lead guitar ) , Tim Commerford ( bass/backing vocals ) , and Brad Wilk ( drums ) . Brad Wilk . Wilk started his career as a drummer for Greta in 1990 , and helped co-found Rage with Tom Morello and Zack de la Rocha in August 1991 .