Japan’s sprawling rock underground is a strange and wondrous thing, and it’s hard to think of a figure who represents its manic diversity better than drummer Tatsuya Yoshida. In the past he’s played with legendary heavies like YBO2 and Zeni Geva, but he’s best known as the constant in a revolving-door duo called Ruins. Over the years he’s paired off with a variety of technically dazzling electric bassists (the latest is Sasaki Hisashi) to create a mind-fucking fusion of prog, punk, and opera. In August the local Skin Graft label will release the duo’s latest album, Refusal Fossil, rife with the usual high-velocity acrobatics and occasionally climaxing in bits of pure hard-rock firepower. Ruins rarely perform in the U.S., and their live shows are legendary. This weekend we get two of them, and as a special bonus a pair of Yoshida-related Japanese bands will make their Chicago debuts in the opening slots: On Saturday Yoshida performs with High Rise bassist Nanjo Asahito in Musica Transonic, a wailing, punk-inflected instrumental psychedelic unit whose two albums on the Japanese P.S.F. label deliver some of the heaviest, most sublime wah-wah-warped guitar crud you’ll ever hear. Asahito and Musica Transonic guitarist Makoto Kawabata also play in Mainliner (who open on Sunday) with drummer Hajime Koizumi. Though it seems impossible, Mainliner is heavier than Musica Transonic, a terrifying blur of guitar abuse. Saturday, 10 PM, Empty Bottle, 1035 N. Western; 773-276-3600. Sunday, 9 PM, Fireside Bowl, 2646 W. Fullerton; 773-486-2700. PETER MARGASAK

Art accompanying story in printed newspaper (not available in this archive): Ruins photo/ uncredited.