There's an old saying that says "two heads are better than one". Now I'm not certain where that originated, but I wouldn't be surprised if it wasn't referring to the world of popular music. Some of the greatest musical acts of all time were duos. Simon and Garfunkel, Sam & Dave, and Seals and Crofts are just a few of them. Some were real brothers, like Phil and Don Everly, and others just called themselves brothers, like Bill Medley and Bobby Hatfield or "The Righteous Brothers", as we know them.