Pittsburgh, PA’s The Don (as they’re known in some circles) have been around since 1991, and took a road barely traveled at the time: they didn’t bother with vocals and lyrics, but focused instead on hard angles, shifting time signatures and bludgeoning guitars, and cultivating an improv aesthetic accented with carefully placed clutter and crunch. Over time, the band changed both labels and line-ups (only founder/drummer Damon Che remains, but he’s the crucial core of the Don’s sound), and on Punkgasm, they’ve added vocals, to the dismay of some hardcore fans. But they work fine for the most part, sprinkled lightly on a few tracks, and worked into the mix with a levity. While there are moments of sheer textural delight (such as percussive hot spot “S*** Kids Galore,” the funky “Bulk Eye” and “Awe Man...,” the hazy “Celestial Dusty Groove,” or the guitar onslaught that is “Slaughbaugh’s Ought Not...”). The pièce de résistance is the nine-minute protean opener, “Loudest Shop Vac In the World,” a beautiful, rhythmic and flowing math-rock epic that builds and fades and builds again in a wash of sounds alternately delicate and graceful, brawny and menacing. A great way to meet The Don.