Many folks will stick with "a-tonal." The Luttenbachers hover where free-form death metal and free-form avant-jazz (again with the hyphens) collide, as if the band's onstage, playing for exactly one person, who keeps transmogrifying from a jazzbo to a stoner to an indie rocker to a mullethead to Captain Beefheart to Dick Dale to Animal (drummer, icon, Muppet). The music shapeshifts accordingly, posing a dire threat to your eardrums, your sanity, your peace of mind, your lunch.
Drummer/composer Weasel Walter and his ever-revolving pie rack of cohorts have logged a lot of practice at this -- 10 years, actually, in the thriving multi-hyphen Chicago jazz scene. Big shots like Ken Vandermark have floated in and out, but mostly the Luttenbachers are young, hungry unknowns credited with playing instruments like "earth bass" and "air bass." (Sadly, there is no "water bass.") Brainiac jazz factors into it, sure, but with menacing bass/guitar distortion, Walter's maniacal pounding, and song titles seemingly lifted wholesale from Slayer albums ("Infektion," "Demonic Velocities," "Storm of Shit," "The Critic Stomp"), an open-minded Cannibal Corpse fan could get down to this just fine.
Verdict: This here's flamethrowing instrumental jazz-metal hoo-hah, a band of Yoko Onos infused with testosterone who don't sing. The Luttenbachers didn't break up the Beatles, but they could've broken the Beatles into little hyphenated pieces.