Pittsburgh’s Derek Vanetti is the songwriter, guitar player and frontman of this secular choir, a preacher with a message that touches on salvation, damnation and the many shades of belief that exist between atheism and religious conviction. His shaky vocals often sound like they’re about to shatter into fragments, but he manages to hold it together with an invigorating combination of humor and anger. Vanetti opens “Seasonal Depression” with his acoustic guitar and a glum vocal as he describes the downward spiral of college debt, aging and playing in a band that nobody listens to. Banjo and slide guitar add a brief country flavor to the music before a wave of distorted punk noise crashes down to deliver a bracing jolt of righteous fury. The rapid shifts between the quiet rumination of “Sometimes” and the deafening power of “Crazy” mirror the turbulent emotions the Homeless Gospel Choir expresses with unbridled grace and power.