jazz

Sure, they get dressed up in black ties and trotted out in concert halls these days, but John Zorn's ADD-addled collage compositions will always fit best on Saturday mornings with a bowlful of sugary cereal. Heavily inspired by Carl Stalling's Looney Tunes scores, Zorn best captures that gleeful rigor (or is that rigorous glee?) in his game pieces, guided improvisations played by obscure rules meant to force a roomful of musicians to function like the composer's hyperactive brain. With colored cards prompting various combinations and musical ideas, Cobra is often more fun to watch than listen to, making literal the idea of "playing" music. The aural equivalent of William Burroughs' cut-ups, performances test the reflexes, as musicians are forced to formulate and execute ideas instantly, before the piece takes yet another right-angle twist. Trombonist David Blacksberg leads a dozen local Philly improvisers through their paces at the Rotunda.

Fri., Oct. 21, 8 p.m., free, with The Sublimator and Jean Benoit, part of the Gateway to Moonbase Alpha series, The Rotunda, 4014 Walnut St., www.foundationarts.org.