Stanley steers well clear of these classical pioneers (even those, such as Kurt Weill, who dipped a lot more than a toe into popular music), but does an inspired job of identifying and describing all the tangled roots of pre-rock popular music. He’s not pompous enough to put forward anything as scholarly as a thesis — but a sort of thesis emerges anyway. It’s that, for the first time in history, technology became the driving force behind music’s development.