Two months ago or so with no prior knowledge of the dude or his tunes -- I checked out 21-year-old British blues-rock prodigy Davy Knowles playing a free show in Philly, and I was utterly blown away. His touch on the fretboard was deft and effortless; his solos, clearly influenced by Stevie Ray Vaughn, were outrageous; his voice was resonant, gritty, and assured; and his band, Back Door Slam, kept things tight and propulsive like a 21st century Double Trouble. I later learned that Knowles, a native of the Isle of Man, fell in love with music via Dire Straits Sultans of Swing, then devoted his young life to learning the blues by way of Robert Johnson, John Mayall, Peter Green, and Eric Clapton. His talents eventually caught the attention of Peter Frampton, who co-produced his new Coming Up for Air. Like Jonny Lang and Derek Trucks before him, Knowles deep understanding of the blues belies his youthfulness. And man, the kid can shred.