Slowhand's catalog is saturated with blues feeling. He stretches out on the fretboard when interpreting songs from the Americana songbook, as on Cream's 17-minute, electrified, and kaleidoscopic journey through “Spoonful.” With a duet version of “Key to the Highway,” recorded alongside his idol B.B. King, Clapton proves that he's equally adept at taking an acoustic approach to a vintage cover.