The word "orchestral" gets dropped every time some cruddy indie-rock band crams a tuba solo or two-part harmony into one of its songs. But few auteurs of underground pop have as much conceptual chutzpah as Dave Longstreth, the nucleus of the Dirty Projectors. Layered with beauty and skewered by weirdness, Longstreth's string of releases over the past four years have plumbed just about every tone, melody and genre imaginable, all the while remaining tied to a shaky folk core that swings without ever flying off the hinge. As reductively grand and deceptively dense as his arrangements can get, though, his voice is the kicker, an unscratched itch of a croon that seeps out in a dozen dimensions at once. Longstreth is currently touring with a loose handful of backing players in support of his latest EP, New Attitude, which should prove to be yet another brick in the Dirty Projectors' warped, magnificent wall of sound.