The Beatles changed everything—the sound of music, the fashion, the politics, even the idea of what a band could be—and they did it across a span of just seven years. To dig into the guitar playing of John, Paul, and George, we called on Jimmy Vivino, longtime member of Conan O'Brien's house band and a guy who's done the deep forensic work of recreating later-period Beatles material with the Fab Faux.