While Avicii's bold move left some scratching heads, it makes more sense through a wider lens of musical trends in the last couple of years. Bluegrass and banjos have become normalized within pop music through a type of act almost as surprising as a Swedish DJ/model: a British folk band.

Mumford & Sons tapped into one of the same specific sources of inspiration as Avicii: the O Brother, Where Art Thou? soundtrack. Marcus Mumford and co. have publicly acknowledged the 2000 movie's music, which was led by its hit single, a cover of "Man of Constant Sorrow" by the film's fictional band the Soggy Bottom Boys. And it was lead Soggy Bottom Boy � bluegrass great Dan Tyminski � along with another unlikely collaborator (Incubus guitarist Mike Einziger) who helped Avicii find his inner twang on True, the album featuring "Wake Me Up."