This septet, engineered to pivot around Chicago keyboardist Dan Trudell’s sturdy Hammond B-3 organ, cranks out a whole lotta funk and just as much fun. Trudell is probably best known for his Sunday-morning services at the Green Mill: from midnight till 4:30 AM he anchors the Sabertooth Organ Quartet, spreading motile comp work behind the band’s dual saxophone front men and bubbling up into swirling, expansive solos of his own. (At times he reminds me of Larry Young, and I can think of no higher compliment for an organist.) For the Bombers, Trudell has borrowed one of the Sabertooth’s saxists, Pat Mallinger, heard here on alto; added New York tenorist Doug Lawrence, guitarist Mike Standal, and trombonist Joel Adams; and tweaked the mix with occasional contributions from a rapper who calls himself, humbly enough, “Elo Heem.” But it’s the presence of drummer Clyde Stubblefield–famed for driving late-60s James Brown classics like “Cold Sweat,” “Say It Loud,” and “Funky Drummer”–that makes the real difference. With devastating fills and unexpected polyrhythms, Stubblefield ruthlessly exploits the beat he helped invent in his days with Brown, in the process marrying the Bombers to the roots of their chosen form with a directness unique among latter-day funk outfits. With their darkened harmonies and Trudell’s baggy, low-slung bass lines, the Bombers occasionally nod to the jam-band scene–but they don’t cross the line into the flattened, affectless posturing that mars so much of its music. In general they hew to the sharper, cleaner edge of more traditional funk, informed by the saxophonists’ strong jazz backgrounds, and Stubblefield’s incisive strokes lead the charge. The Bombers have just released their debut disc, Live at the Green Mill (Alltribe); they return to the scene of the crime for these CD-release gigs. Friday, May 10, 9 PM, and Saturday, May 11, 8 PM, Green Mill, 4802 N. Broadway; 773-878-5552.