Baritone vocals are difficult to pull off in pop music. There's an inherent darkness in words sung through such a sobering lower register. For Matt Berninger and the band called the National, there's beauty to be had in so many grim, lightless corners. Delivering the kind of lonesome warmth typically reserved for Leonard Cohen with the instrumental drama of Arcade Fire, the National experienced its biggest success with its 2007 “The Boxer,” landing on numerous best-of lists in the independent music community. With the band's anticipated follow-up, “High Violet,” scheduled for release in early May, the Brooklyn-based collective has decided to make an extended stay at Richmond's aptly named venue starting Thursday, April 22, at 7 p.m., playing at the same time Friday, April 23.