Like the similarly prolific Ryan Adams, Conor Oberst has often insisted that he’s just a guy in a band, and that even though he writes nearly every song he sings, his work is largely collaborative. Oberst backs that boast with Outer South, a record credited to him and his touring group The Mystic Valley Band, and featuring multiple songs written and sung by mates Taylor Hollingsworth, Nik Freitas, and Jason Boesel. The bad news? While the non-Oberst material is hardly terrible, it’s largely undistinguished, relying often on cutesy hooks and drippy sentiment. The good news? Oberst’s songs sound that much better by contrast. On stompers like “Slowly (Oh So Slowly)” and “Nikorette,” Oberst reverts to the loping country-rock he pursued so fruitfully on the Bright Eyes LP I’m Wide Awake, It’s Morning, while on the spare ballad “White Shoes” he gets back to the cranky-loner-with-guitar mode that used to be his bread and butter, spitting out confessions and repeating phrases as though he were delivering a benediction. Oberst just sounds more energized than he has in years on Outer South, while still producing songs that roll out smoothly, buoyed by catchy choruses, memorable lines, and some of the most spirited singing and playing of his career. Maybe there’s something to this whole “band” concept after all.