San Francisco jazz duo Tuck & Patti will perform live on March 6 at St. Matthew’s Episcopal Church in Wilton, but to call it jazz may be to detract from what is perhaps in reality a more eclectic style and a less specific sound.

She and her husband are “improvisers,” said vocalist Patti Cathcart. “Both of us have our roots in jazz tradition in that we do improvise, but we explore a lot of different kinds of music with Tuck & Patti.”

Tuck Andress, who plays guitar in the duo, can trace this sense of experimentation all the way back to Tuck & Patti’s inception, which predates his and Cathcart’s marriage by three years.

“When Tuck & Patti first got together, now over 37 years ago, we discovered that playing in a duo — which neither of us had ever done previously — can be incredibly liberating in terms of style,” Andress said.

“We found that we didn’t need to decide on a style; everything seemed to sound like us. We’re a vocal and guitar duo — for some reason, that has this magical effect of reducing the need to consider style.”

Andress first met Cathcart when she auditioned for a San Francisco band he had been playing in at the time.

“There were a lot of great players, but it only lasted a couple of months,” Cathcart said. “Meanwhile, Tuck and I had become best friends.

“It was nothing romantic yet, but I loved his playing from the moment I first heard it. Well, he loved my singing, too, so I said, ‘Let’s get a gig as a duo and then put together our own band.’

“The day we met, we started playing music together, then three years later, we got married,” she said.

Over the next three and a half decades — years interspersed with record releases and global tours — Tuck & Patti’s signature style would grow to encompass genres that now range anywhere from “jazz, rock, pop, and Brazilian” to “soul, classical, and imitation flamenco.”

While both Andress and Cathcart were hard-pressed to label under one genre-head the musical style of Tuck & Patti as a group, each had plenty to say about the other’s musicianship.

Cathcart is impressed by her husband’s signature meld of influence. “Tuck is one of the most amazing musicians I’ve ever played with,” she said. “What he brings to the guitar has been a revelation.

“It’s rock and roll deeply rooted in jazz; it’s folk music with Brazilian touches, it’s Jimi Hendrix; it’s Duke Ellington, Aretha Franklin, the Rolling Stones — it’s a little bit of everything.”

Andress, on the other hand, takes pride not only in his wife’s technique but in her ability to transcend that technique in live settings.

“What I hear in Patti’s voice from the standpoint of literal vocal quality is a beautiful balance of tones,” he said. “It’s a really beautiful voice. But there’s another thing that I think is more important, and it’s what we take away from hearing Patti sing as listeners.

“I don’t quite understand the process, but Patti can go direct heart-to-heart with her audience, as if she were having an impassioned conversation with her best friend. That, to me, is the magic of Patti. I can admire her technique — it’s dead-accurate — but it’s all in service of this greater thing.”

When Andress and Cathcart aren’t writing, recording, playing live, or touring, they’re teaching and producing musical projects in their home city of San Francisco.

Tuck & Patti’s concert at St. Matthew’s Episcopal Church is one of three scheduled for the East Coast before the duo heads to Europe.

On March 6, audience members can expect Tuck & Patti to play previously unheard material from their next record. Each audience member will be given a card with a Web address they can visit to download rough mixes of these yet-to-be-released tracks.

“We always honor requests, too,” Andress said. “Even if it’s a song we’ve never played before, we’ll try anyway.”

St. Matthew’s is at 36 New Canaan Road. Showtime is 4 p.m. Tickets may be purchased at ArtsatStMatthews.org. Regular admission is $35. Patron seating is $70 per person.

Information: ArtsatStMatthews.org, TuckandPatti.com.