As much as this quirky Seattle outfit riffs on the sounds of indie rock of recent years, they’ve also developed quite an affinity for the tenets of prog rock. Songs that run a little long, have an orchestrated, complex feel and generous doses of strings, keyboards and shifting signatures are all in prog’s DNA, and blending that genre with the former is the path apparently taken by MSHVB. A song like “Hurrah,” done by, say, Modest Mouse, would do without the white spaces and throw more solid punches: but MSHVB takes their time, launching dramatic arpeggios (wrapped in strings!) and repeated, concrete-hard chunks of percussion and guitar grenades to reach its satisfying end. Listeners are advised to resist attempts to puzzle out the meaning of it all (the band name? their mysterious backstory? is this a concept album?) and just go along for the crazy ride. The ‘70’s flourishes of “At Night,” the vaporous vocals and shadowy cello parts in “Bitter Cold,” and the dramatic flights of synths, strings and guitars on “You Were/I Was” are what one hopes for from a group with a name like Mt. St. Helens Vietnam Band.