A funk band without a good bassist, like a three-legged racehorse, isn't worth the trouble. George Porter Jr., an original member of the Meters and an in-demand freelancer, is one of the genre's greatest bassists. Part energizer, part hypnotist, the lifelong New Orleanian can make a fast blues run or a rumbling chord sound at once like a threat and a joke, and make a four-note ostinato sound like a mantra and a come-on.

True, he's not only a funk bassist; he plays jazz, rock, soul, zydeco ... we could go on. His versatility will be demonstrated by two Twin Cities gigs in the coming weeks: first this Friday at Trocaderos with funk-rock trio Porter Batiste Stoltz, soon after with jazz guitarist John Scofield at the Dakota. (Plus he was at the Cedar in late February jamming with Dean Magraw and others.)

That versatility noted, we might add that funk is not just a genre but a worldview, hard to shake, once adopted. Lee Dorsey summed up the credo back in '69 with his single "Everything I Do Gohn be Funky (From Now On)," a pledge made all the more convincing by Porter's spare bass line.

Porter, 61, played his first gig when he was in his early teens (at a church; he made $1.50). By the mid-'60s he was performing R&B in nightclubs, and at seventeen was spotted by singer/keyboardist Art Neville, who'd been playing on regional and a few national hits for a decade.

"The first time I met Art, I was a guitar player," Porter said by phone from his home in New Orleans. "And he hated me as a guitar player. Then he saw me play bass one night, and said, 'Now, that's what fits you.' Playing with him, I thought, I may have a shot at going outside of New Orleans -- maybe get to Baton Rouge."

Neville, Porter, guitarist Leo Nocentelli and drummer Joseph (Zigaboo) Modeliste eventually became the Meters, and were tapped as a house band by producer/musician Allen Toussaint. With the Meters and on his own, Porter has supported dozens of N.O. greats, as well as Paul McCartney, Tori Amos and others. (For his recent work as sideman, check out Scofield's gospel-blues album, "Piety Street," out March 31.)

By '69, the Meters were recording under their own name, scoring hits with instrumentals such as "Sophisticated Cissy," later moving to Reprise Records and adding more vocals. Variously elegant and silly, casual and urgent, the Meters' records are full of dreamy melodic figures, ornery unison riffs, second-line syncopation and some of the most rhythmic space ever left unfilled.

"When I started out, I was very busy player," Porter said. "But the older I got, the more I understood what Allen was always saying: It's not what you play, it's what you don't play that makes the groove. And I live by that now. Although I still like being busy sometimes. Sometimes in a power trio being busy is OK."

The power trio in question is Porter Batiste Stoltz, a collaborative group Porter shares with guitarist Brian Stoltz and drummer Russell Batiste. The three first teamed up 15 years ago in the Funky Meters, a Meters offshoot popular on the club and festival circuit. Though the New Orleans funk tradition is their foundation, PBS is a rock trio as well, particularly indebted, largely through Stoltz's influence, to the blues Cubism and cloud zebras of Jimi Hendrix. The mix has proved popular with younger crowds on the jam-band scene.

"I'm playing to almost the same age group I played to 42 years ago," said Porter.

Live, the group mostly plays originals (each member sings and writes), but also refashions rock and R&B tunes ranging from Pink Floyd to Lee Dorsey, and their latest album, "Moodoo," a live set co-starring Phish keyboardist Page McConnell, has a version of "A Message from the Meters," reworked as "A Message from PBS."

Porter and Batiste's long working relationship, as with Porter's work with Modeliste, has led to the two-heads, one-mind simpatico rhythm sections strive for.

"My job is to play with the drummer, not him play with me," said Porter. "The two things in the drum kit that I want to hear is the high-hat and the kick drum. With the high-hat, I always know where one is; with the kick drum, I always know the syncopation.

"When I'm really paying attention, I almost know where the drummer's going, and I'm on top of him like butter on grits. When we're all listening like that, that's when it's magic. Sometimes we're playing, and we all look at each other and just laugh, 'cause we all did something from outer space at the same time."