Wheels of Fire was a two-album set, one disc recorded in the studio, the second disc recorded on stage in San Francisco. Side three contains the definitive live version of what became Clapton's signature piece, Robert Johnson's "Crossroads," plus a version of "Spoonful" that clocks in just short of 17 minutes. On such pieces, Cream approached blues-based rock with a jazz aesthetic, using the song as a framework to begin and end a performance. The strength of the performance is in the improvisation. When it worked, as it does on "Spoonful," they were brilliant. When it didn't, as on "Traintime" and "Toad," the band became excess incarnate. The studio disc contained their second Top Ten single, Jack Bruce's "White Room," as well as a stunning cover of Albert King's "Born Under a Bad Sign." Other tracks, particularly those written by Ginger Baker, do not hold up.