The technique of this composer and performer was so frightfully good that many claimed that he was in league with the Devil. Giving his first public recital at the age of 12, early success proved to be nearly insurmountable. His favorite violin was the so-called il cannone, or the "cannon," crafted by famed violin maker Guarneri. His flashy first violin concerto is filled with deft maneuvers like left hand pizzicato, rapid thirds, and an abundance of harmonics. These techniques led many of his contemporaries to call the concerto unplayable. This criticism only seems to have helped cement his reputation as a peerless performer.