If the progressive rock of the 70s was a bloated red giant, then the Ruins are the compact, whirling pulsar left behind after the supernova. This bewildering Japanese duo uses only a drum kit and an electric bass to create a frantic, overstuffed conglomeration of dense hyperspeed prog, alien funk, blown-out metal, and batty histrionic art-rock, peppered with blurts of blistering thrash, labyrinthine meterless unison passages, and goofy, catchy melodies that sound like Gypsy music from the planet Kobaia. Both members sing in an invented language, bleating, sputtering, growling, and crooning, and because the bass doubles as a MIDI controller some of the songs are even gilded with layers of ersatz piano or pizzicato strings. The Ruins' most recent disc of new material, 2002's Tzomborgha (Ipecac), also includes a mutated Messiaen melody, a cover of a tune by south Indian fusion violinist Lakshminarayana Shankar, and two ridiculous medleys--one devoted to the Mahavishnu Orchestra, the other to Black Sabbath--that pack tiny snippets of a couple dozen songs into less than three minutes. (This show is in support of this year's remixed and expanded Skin Graft reissue of Vrresto, originally released in 1998.) Drummer Tatsuya Yoshida has worked with four bassists since founding the Ruins in 1985, and last year his longest-term symbiont, Sasaki Hisashi, left the band--hence the current "Bassist Wanted Tour." At each stop a courageous local will attempt to re-create the near psychic connection Yoshida has always developed with his bassists; in Chicago it's Jonathan Hischke, currently a touring member of Hella and formerly of the Flying Luttenbachers. He's learned ten songs and also plans to improvise with Yoshida, and the drummer will likely play a few tunes along with a taped bass part as well--a feat of concentration comparable to studying a video of Nightline until you can blink in sync with Ted Koppel. Opening is the Saint Louis trio Yowie, which high-steps through a thicket of stiff, spiky, atonal insect prog on last year's Cryptooology (Skin Graft); Hischke, apparently a glutton for punishment, will fill in for recently departed guitarist Jeremiah Wonsewitz. Big Business plays second. Fri 7/22, 10:30 PM, Bottom Lounge, 3206 N. Wilton, 773-975-0505 or 866-468-3401, $10 in advance, $12 at the door, 18+.