On his latest, Here We Rest, Jason Isbell (and his band the 400 Unit) crafted something special. It’s a riveting album, exuding loneliness, intelligence and, as always, a certain sly confidence. Whether it’s the protagonist of “Alabama Pines” hanging out alone in a motel room, the narrator of “Stopping By” planning an encounter with his deadbeat father or the worn-out soldier in “Tour of Duty” who’s adjusting to life on the home front, these narratives examine the quest for something just beyond reach. Of course, there’s a direct line back to “Outfit,” Isbell’s classic from his days with the Drive-By Truckers (not to mention “The Magician” and “Soldiers Get Strange”). He is a master of capturing, distilling and elevating a particular breed of ennui suffered by smart, soulful Southern dreamers — and it doesn’t hurt that he’s one of the most affecting guitar players around.