Portland's Blitzen Trapper take the stage at the Troubadour tonight with countrified indie rock. The sextet's third release, last year's Wild Mountain Nation, is a collection of lo-fi ditties that convincingly walk the line between Appalachian twang and the playful style-experiments of Pavement's Wowee Zowee, with a few classic-rock riffs thrown in for good measure. Riding a wave of positive reviews and well-deserved Internet hype (including Pitchfork's all-important  Best New Music nod), the band signed with Sub Pop last summer. Gentle indie-pop group Grand Archives and atmospheric folk-rockers Fleet Foxes open.