There are reasons why the angels in old Renaissance-era frescoes are always toting horns, and they aren't all biblical: Blown just so, brass instruments have a way of setting a tone, inducing feelings -- from reverent to melancholic and back again. PW3, one of Denver's more successfully nebulous outfits, folds horns of all kinds into its soundscapes alongside muted guitars, a restrained bass and drums that rattle around the rim of your listening space -- and your consciousness. Melodic, daring but never opaque, the five members of PW3 aren't bound by any kind of genre considerations; instead, they riff off a freedom to do whatever they please by sometimes slowing down for truly cool, free-range jazz provocations or cranking up for distortion-laden, driving instrumentals. A headlining appearance at the Bug Theatre on Thursday, February 28, with Andy Monley opening, will find the band (formerly known as the Perry Weissman 3) in an environment that does justice to their artistry. Do the Weiss thing.