The way the rock business works is, you buy the record and if you like what you hear, you go to see the band in concert, which more likely than not, will be scheduled within two months of the record's release. Or, you see a band (by accident?) at a concert and then you rush out to your nearest record store, buy the album and are immediately disappointed. In Japan, you can usually buy it in the lobby.

At least, that's the way I think it's supposed to work. In any event, The Mars Volta's concert at Shibuya Club Quattro on April 6 was not business as usual. Formed partially from the ashes of At the Drive-In, the El Paso, Texas, post-punk band whose stunning 2000 album, "Relationship of Command," impressed even the most jaded rock-watcher, The Mars Volta managed to pack Quattro despite a total lack of locally available aural product.

Which isn't to say sounds weren't available, only that those sounds were limited to MP3 recordings of songs from their European tours, with titles that seemed to change by the hour. The band's first EP wasn't on sale until three days prior to the Quattro show, which meant you couldn't find it at any local record stores. When you could dig up a description of the music itself, you read about influences as wide-ranging as Led Zeppelin, Fela Kuti and salsa; or that the band was an offshoot of a dub-electronica project called Defacto. In its press release, the Japan tour promoter likened their sound to prog-rock dinosaurs like Yes and King Crimson.