Sturgill Simpson’s ‘A Sailor’s Guide to Earth’ is the rare album that traverses the entire world, both musically and lyrically. It’s dizzyingly diverse, jumping from one style to the next, with ports of call in Motor City and Music Row, Harlem and Stax, Berlin and London, yet it never leaves Simpson’s very specific point of view. It’s his most personal album as well as his most ambitious: a song cycle penned as a sailor’s poignant letter home to the wife and child he left behind.