Seattle trio Posse emerged in 2010 with the release of an eponymous CD via the band’s own Beating a Dead Horse label, followed by 2014’s wryly titled Soft Opening LP. The outfit garnered attention for spare, economical indie-pop, distinguished by the deadpan, unbothered interplay between co-vocalists Paul Wittman-Todd and Sacha Maxim. But Posse’s latest song, “Voices”, expands the same template, resulting in a melancholic, skeletal ballad that withholds eruption for over six minutes and finally bursts. In a worse song, the arrival of an anticipated pop payoff might render the buildup somewhat moot. Here, the slow-mounting tension is its own reward. “Voices” is taken from the Perfect H 7-inch, due next month via Wharf Cat.