We all love music, but most of us run in the other direction when anyone mentions music theory; the actual nuts and bolts of it are enough to make most people’s head explode. Until now that is. Author John Powell remedies the situation with his new book “How Music Works: The Science and Psychology of Beautiful Sounds, from Beethoven to the Beatles and Beyond.” Powell does the impossible: he explains the science behind music in terms that anyone can understand. Plus, he interjects enough humor to turn this into a real page-turner. Icon Fetch talks to the author, who is also a physicist, about what distinguishes music from noise, what makes an “A” note, and why ten violins playing together is only about twice as loud as a single violin.