For 20 years, Kurt Wagner, the creative force behind the ever-expanding and contracting Nashville collective Lambchop, has created beautiful and confounding music. His husky voice sing-speaks phrases both banal and profound, making the everyday seem grand and mysterious. Existing comfortably outside the mainstream, Lambchop’s music has touched on a number of styles – country, soul, jazz, lounge – with each of their eleven albums evincing its own distinct mood and atmosphere. On the latest, Mr. M, swelling strings add a sweet elegance to Wagner’s sometimes gruff ruminations on life and loss – dedicated to his friend and collaborator, the late songwriter Vic Chestnutt. Lambchop performs in support of the disc at 8 p.m. at the Ark, 316 S. Main St., Ann Arbor; 734-761-1451; $20; with Kelly Jean Caldwell.