The Moaners release Nocturnal at Nightlight Saturday, Sept. 18, with Ryan Gustafson. Steph Russ deejays. The 10 p.m. show costs $5.

To say that Melissa Swingle’s voice isn’t what one would call pretty would be an understatement. Some might even go so far as to describe it with the sort of backhanded compliments reserved for overselling a blind date prospect”Oh, it’s got a great personality and a fantastic sense of humor, too.” But ever since her days fronting off-kilter country swingers Trailer Bride, Swingle has willfully embraced her voice’s quirks: the hitch in its giddyup when she reaches for certain notes, the way it curls around specific sounds like a three-legged cat, the world-weariness its smoke-laden drift carries. And while not much has changed in Swingle’s music over the past 15 years, except the number of co-conspirators, it’s within the decidedly less cluttered confines of The Moaners that her voice has sounded most at home.

On Nocturnal, The Moaners’ third and most varied album, Swingle and drummer Laura King preside over a set of songs as idiosyncratic as their frontwoman’s delivery. It’s evident right from the opener, “Humid Air,” which gleefully commingles Swingle’s slow-handed slide work with a surprising drum-machine beat. The presence of Johnny Cash band member Earl Poole Ball on piano is something more expected, but The Moaners make sure to keep him on his toes. He rollicks with the ivories during the bluesy bank heist goings-on of “Cowboy Bob,” while the ramshackle “Raggedy” features Ball in a more contemplative and relaxed mood.

Nocturnal brims with “cautionary tales of bad whiskey” (as Swingle calls them on “Bartender’s Lament”), but even those show some unexpected range, from the bemused request for a telephone breathalyzer on “Ramblin’” to the despondent narrator in “Moonshiner.” “If whiskey don’t kill me / I don’t know what will,” Swingle sings. And whether she’s offering some haunting, arcing fragments of slide guitar during “Barbarian in China” or intoning a quaint and plainspoken lullaby in “Little Man,” Swingle never sounds out of her element. Nocturnal is the work of a band comfortable in its own skin. Conventional definitions be damned; that’s a beautiful thing to hear.