The members of jazz fusion group Garaj Mahal draw inspiration from diverse places ranging from rock and funk to Indian and DJ music. But on the ambitious quartet's new and best album, "Woot," they borrowed rhythmic ideas from an unlikelier source - a swamp.

"Semos," the CD's opening track, unfurls behind the primal, bizarre mating call of frogs. The San Francisco-based band was struck by the sound while performing at a gig in North Carolina.

"It was pocketed," guitarist Fareed Haque explains. "The syncopations between the three different frogs was like, happening."

The members of Garaj Mahal, who had been agonizing against a 5/4 meter on "Semos," realized they needed to follow the frogs into 5/2, Haque says.

"It all ended up lining up," he explains. "We were like you're (bleeping) kidding me!"

It's a testament to the rhythmic genius of nature, as well as Garaj Mahal's open-minded approach to exchanging sophisticated, organic musical ideas.

The band of instrumental virtuosos - Haque, bassist Kai Eckhardt, keyboardist Eric Levy, and drummer Alan Hertz - sometimes improvises on a level that traditional music fans might find too intense for their brains to process, much less enjoy.

Consequently, Garaj Mahal sizes up crowds, Haque says. If the Jazz On The Grove audience on Friday, Sept. 5, doesn't seem up to swamp frog rhythms, Garaj Mahal is capable of playing an entire set of more conservative jazz. (Let's hope not, though.)

Garaj Mahal creates its set lists on stage in round-robin fashion; each member takes a turn deciding what song will be played next.

It makes for an interesting, fluid concert vibe, Haque says. At least most of the time.

"There definitely are moments where someone will call a tune, and everybody else in the band is, 'What? You want to play that?'" Haque admits with a chuckle.

Expect the group to focus on material from "Woot," which includes everything from groove-heavy fusion ("Semos") to New Orleans-flavored jazz ("Uptown Tippitinas") and spacier grooves ("Pundit-Ji").

Fans of fusion great Weather Report should appreciate Garaj Mahal's modern-day commitment to experimentation and improvisation on stage. People unaccustomed to witnessing top-notch musicians from a technical perspective may be shocked. (Eckhardt's effortless bass flurries, in particular, tend to dazzle newcomers.)

Pretty much anyone with a toe to tap will appreciate Garaj Mahal's commitment to a groove. This is a band that finds funk everywhere - even, perhaps, in frogs.

Which invites, of course, the obvious question: Exactly what variety of magic mushrooms were these dudes ingesting when they became one with the frogs in North Carolina?

"There were no mushrooms involved," Haque insists with a laugh. "Not that I have anything against mushrooms."

Michael Deeds: 377-6407