Clocking in over 20 years as a band, California punk/ska combo Rancid remains as committed to haunting indie alleys as when buddies Tim Armstrong and Matt Freeman were in the hugely influential Operation Ivy in the late '80s. So what if Rancid's contemporaries Green Day and the Offspring went on to huge mainstream success? During that period in the mid-'90s Rancid burrowed further into the underground, thumbed its noses at major labels when they came bearing wads of cash and stayed with Hellcat, an offshoot of indie Epitaph Records, exponentially upping its street cred. Rancid has been fusing a love of late-'70s punk, especially The Clash, and an ear for ska and reggae since the early days. The band's not too shabby playing acoustic on occasion, as it morphs into a roots band for brief moments. But expect plenty of old-school punk ditties - most lasting less than three minutes, of course. Guitarist and lead vocalist Armstrong's alter ego Tim Timebomb will warm up the crowd as he welcomes musician friends and plays mostly acoustic and some instrumental versions of country, roots, punk and ska covers, plus some originals. The Interrupters and Patriot are also on the bill. $33. Sept. 10, 7 p.m. The Fillmore, 1000 N.C. Music Factory Blvd. 704-916-8970.