“Rare and Unreleased” promises so much, and the CDs bearing the phrase rarely deliver. The results are often for completists and scholars, and Aretha’s s Rare & Unreleased Recordings from the Golden Reign of the Queen of Soul keeps the string alive. There’s nothing here to make you think a song was unjustly omitted, or that they got the wrong take. It’s instructive to hear how demos became fully developed songs—often by picking up her tempo and dialing back her church-isms—and it’s a pleasure to hear her play with the songs, including a significantly jazzier “Fool on the Hill.” Because this is Aretha in her prime, there’s still a lot of powerful music here, and her throwaways are better than a lot of keepers. Still, she made a lot of music more necessary than this.