Instability was a constant throughout Savage Republic's decade-long career--they had a different lineup on every one of their four studio full-lengths and often sounded like a different band from song to song. Tragic Figures, their 1982 debut, ranged from apocalyptic rants set to the rattling shudder of massed scrap-metal percussion to ultracatchy guitar tunes that sounded like Glenn Branca fronting the Ventures; Customs, their 1988 swan song, mixed Einsturzende Neubauten clang and Flipper sludge and threw in a handful of lilting, Aegean-tinged acoustic instrumentals. Ethan Port, Greg Grunke, and Thom Fuhrmann, core members from '83 onward and regular collaborators since the band's demise, inadvertently clarified one reason for that instability in 2002, when they resurrected Savage Republic for a week to support a box set of reissues: though they attacked their old songs with gleeful ferocity, they looked so different from one another you hardly would've expected to see them in the same club, let alone on the same stage. Lean and wild-eyed, Port battered a flaming 55-gallon oil drum like a Bikram yoga instructor communing with his inner arsonist; the beefy Grunke, his head wrapped in a bandanna, could've passed for the token old guy in a classic-rock cover band. And Fuhrmann, who handled most of the vocals, cut an incongruously randy figure with his low-slung bass and Gene Simmons-style extendo-tongue action. The 2002 shows were billed as a one-off reunion, but Savage Rebublic has since officially re-formed--now touring as a five-piece, they'll have prerelease copies of a brand-new EP called Siam (Neurot/Mobilization) for sale at this show. The disc includes four originals cut from the same variegated cloth as the 80s material and a cover of Echo & the Bunnymen's "Heads Will Roll." Vee Dee, Pink Reason, and the Chord open. a 9 PM, Double Door, 1572 N. Milwaukee, 773-489-3160 or 312-559-1212, $15.