Peter Buck Splinters Into a Three-Band Musical Circus Act

It seems that whenever a band is on hiatus these days, one or more of the members will form a splinter group. In the wake of Banyan (Porno for Pyros’ Stephen Perkins) and Three Fish (Pearl Jam’s Jeff Ament) comes Tuatara, a collective starring R.E.M. guitarist Peter Buck. The band’s recent debut album, “Breaking the Ethers,” is packed with eccentric instruments and jazzy grooves, but rarely feels self-indulgent.

On Tuesday at Barnsdall Art Park’s Gallery Theatre, Tuatara played a sax- and vibraphone-laden show dubbed “The Magnificent Seven vs. the United States.” It was an ambitious, democratic three-ring circus beginning with Tuatara, which later backed San Francisco singer-songwriter Mark Eitzel (whose new album, “West,” was co-written and co-produced by Buck) and then transmuted into the group the Minus 5--yet another Buck side project.

Then they did the whole thing over again, turning an intriguing prospect into a three-hour marathon that was simply too much to absorb.

Tuatara is Buck along with members of the Minus 5 and the groups Screaming Trees, Luna and Critters Buggin (joined Tuesday by Los Lobos’ Steve Berlin and Devilhead’s Mike Stone). Their instrumental blend of jazz, Latin rhythms and spy-movie soundtrack felt beguiling and seductive during the first round, but devolved into relentless, long jams during the second. The Minus 5, despite some catchy, jangling tunes from its new album, “The Lonesome Death of Buck McCoy,” never got its footing.

Surprisingly, the musician who best rose to the occasion was the notoriously downbeat Eitzel. Armed with dark, heart-rending, hard-luck songs about love and cocktails, the former American Music Club leader delivered music filled with pathos and character. But even Eitzel, a fumbling charmer onstage, had a hard time picking up the pace the second time around--it was just far too much of a good thing.

* Tuatara, Mark Eitzel and the Minus 5 perform tonight and Saturday at the Ash Grove, 250 Santa Monica Pier, Santa Monica, 8:30 p.m. $15. (310) 656-8500.