Watching Don Caballero can be painful. When Don Cab performs its supercaffeinated metal live, it’s not pretty: The band members attack their instruments with the intensity of linebackers in the midst of a blitz. Many of the fans—baby-T-wearing girls or drooling, skinny boys with fogged horn-rims—are sweat-soaked. And the smell—I can’t fully describe it, but it reminds me of old, crusty socks. But, man, the music: American Don, the Pittsburgh-bred band’s newest album, cuts out heavy riffs to weave an almost delicate fabric of bass and guitar loops backed by drummer Damon Che’s ever-crazy pounding. Imagine the Monsters of Rock puttin’ out an album of amped-up fingerpicking; it’s as if Don Caballero had created roots music for Western Pennsylvania. Now, the quartet will untwine its DNA to perform four separate solo shows for tonight’s Black Cat gig. As always, expect a difficult show. But difficult in a good way. At 8:30 p.m. at the Black Cat, 1831 14th St. NW. $8. (202) 667-7960. (Jason Cherkis)