Sgt. Pepper turns 50 with a new mix

Sgt. Pepper’s Lonely Hearts Club Band may not even be the best Beatles album — in fact, I’d suggest the White Album is, song for song, a better collection. But there is a case to be made that it is the most important album in the history of rock ’n’ roll.
There is very much a pre- and post-Pepper musical world. Released on June 2, 1967, in the U.S., the album almost immediately changed the rules of the game. Sure, there had been impressive albums-as-works-of-art bef