The New Deal is brought to you by the letter "J" and the feverish support of pogoing maniacs, hungry for that most sophisticated of livetronica fixes.

For my time and money, it's the jazz trio-isms which make these ever-more-compelling Canucks the connoisseur's choice among their soundscape-loving breakbeat brethren. You get the feeling more legitimate Jazz Guys with a yen for avant-garde piano (think a Jason Moran) could get hip to this, and Moran would probably be tapping his foot in the background and digging the hell out of the interplay even if he'd never be quite comfortable with the furious pace of it all.

Drummer Darren Shearer and bassist Dan Kurtz tend to yoke Jamie Shields in an unobtrusive way, letting the ground drop out under his crackling keyboard leads and then throwing warped floor under them to draw him in other directions and bait him into tastier jams. Shields is the leader from a melodic standpoint, though, throwing cues both aural and visual at his band mates and steering the ship. He's a manic stylist like Medeski, but his progressions are curved and contorted, with a refreshing absence of chirps and blats.

The tunes mushroom and sprawl, but the band's tightly-knotted focus keeps the inchoate ambience low and the propulsion high; sharp, layered leads wind up at points of throw-the-brakes transition and other times blend more seamlessly into other ideas. "Gnome" was a visceral highlight among the named tunes of this night's show (which also included "Deep Sun" and "Back Off"), and although the crowd was frustratingly spotty—the gorgeous Roxy has always been a tough-to-crack, bigger-than-it-looks palace for jambands ready to burst from smaller clubs—those who did stay til last call gave it their ragingest.

It's tough to keep track of where everything is on paper—the unofficial New Deal setlist archives at www.newdealsetlists.com states in a near-admonishing tone that "New Deal setlists are very difficult to decipher"—and myriad teases and left-field covers (one of tonight's was cheeky version of the theme from "Mary Tyler Moore") crop up to serve as highway cones: brief stops and reference markers to chart the twisty journey.

Overanalyzing livetronica—or anything improvisation-based, for that matter—is a fool's game, but the New Deal prompts a little extra inquiry. Liquid and loose-limbed as those "J's" can be, there's a science at play behind them, and their breakbeat/techno/slow jam/funk turns meld into some sort of musical alloy. It all works, dammit, and at the end of multiple "J's" you feel as though everything's in its right place and the band has arrived at the place it's supposed to have arrived. You catch your breath, and it's up and away again.