Not long ago, the notion of progressive punk seemed oxymoronic. Punk is all about brevity and simplicity, while prog can be drawn out and pretentious. They'd vehemently deny it, but the Mars Volta (led by Omar Rodriguez-Lopez and Cedric Bixler-Zavala, formerly of the post-hardcore experimentalists At the Drive-In) are arguably the first credible punk-prog unit. Their sophomore album, Frances the Mute, is a 77-minute song cycle that hopscotches between electro-salsa, Zeppelin-style gut punches, 20-minute fandangos, and free jazz (imagine a mash-up of King Crimson, Tito Puente, Pharoah Sanders, and Fugazi).
As if the music itself weren't challenging enough, there's the ''concept'': Frances is based on a diary that a late bandmate found in the back of a car. Though the songs (sample title: ''Umbilical Syllables'') are in Spanish and English, exactly what's happening will remain opaque even to the bilingual. Yet the CD has moments of undeniable beauty and power; it may prove to be one of those ''difficult'' records that repays with repeat listens. These days, though, who has the time? We figure the grade's gotta be somewhere between A (for Ambitious) and D (for Daunting); let's call it a