Few, if any, artists transcend genres with immunity. Willie Nelson, Ray Charles, Emmylou Harris - each sings, or sang, with credibility in a wide array of styles, country among them. But Willie Nelson's country is not Hank Williams's or Roy Acuff's. Neither is Charles's or Harris's. That is to say, whether Harris is singing country or rock or a song like "1917" - which sounds like an old Parisian folk song, but is actually a recent work by the American David Olney - it is apt to fall into the comparatively narrow boundaries of Harris music.
That is the lesson of this four-CD, one-DVD retrospective of "rare tracks and forgotten gems," selected by Harris. Like many enduring stars, she is generally defined by her disregard of categories, but it is mostly a false framing. Except, perhaps, when she sings bluegrass - among her most inviting work, including this package's "Get Up John" - it is Harris's voice that is the most distinctive element.
She collaborates here with the likes of Nelson, Mark Knopfler, The Pretenders, George Jones and, of course, Dolly Parton and Linda Ronstadt, but the real guessing game is what style, among the innumerable worthwhile songs, seems most natural to Harris's crystalline - if slightly detached - soprano. The vote here goes to "1917's" tale of a soldier's misery and debauchery.