After more than 50 years of playing together in a confounding variety of settings on a daunting array of instruments, string wizards Jody Stecher and Eric Thompson still find ways to surprise each other.

They join forces again Sunday afternoon at Lafayette's Mighty Fine Guitars in a trio known as Guitars Without Borders. The third musician is Scott Nygaard, who came up on the Seattle folk scene in the mid-1970s studying Stecher and Thompson's seminal bluegrass guitar albums. The triumvirate spun off Thompson's stylistically insatiable quintet Kleptograss when the band's fiddler and bassist couldn't make a gig.

Guitars Without Borders -- from left, Scott Nygaard, Jody Stecher and Eric Thompson -- brings its versatile sound to Lafayette’s Mighty Fine Guitars
Guitars Without Borders -- from left, Scott Nygaard, Jody Stecher and Eric Thompson -- brings its versatile sound to Lafayette's Mighty Fine Guitars on Sunday. (Eric Thompson)

"I said let's do it and (everyone) play guitar, and surprisingly, it really works," said Stecher, whose latest album "Wonders & Signs" focuses on his original songs. "It's not Eric's band. We all choose repertoire equally, and though they're not known for it, both Scott and Eric sing a lot. Eric spent 40 years being a non-singer. He's not just pretty good for a guitar player. He's really enjoyable, which is great to see develop."

While Nygaard's primary Kleptograss responsibilities were on guitar, the band's instrumental concept kept Thompson and Stecher moving between various string instruments. When they played their first Guitars Without Borders gig, they didn't work out arrangements, a risky proposition that could have turned into chaos with less accomplished and accommodating musicians.

"We didn't really think about it until we started," Nygaard said. "The three of us listen really well, and we're pretty comfortable with letting someone else take the lead. You find who's leading the way and make it work, though we have our fair share of train wrecks."

"We do practice quite a bit for a gig, but there are borders to each song," Stecher added. "We agree on the key and the speed, and then every solo is improvised. How we accompany each other too: It's two guitars accompanying a lead guitar, and that is not discussed. It just happens."

A listener may not realize that Nygaard, Thompson and Stecher are essentially creating arrangements and orchestrations on the fly. What's immediately striking about Guitars Without Borders is the stylistically encompassing repertoire implied by the band's name. A typical set will range between blues and bluegrass, Irish reels, field hollers, old-time fiddle tunes, ragtime, Swedish waltzes, Caribbean hoedowns, jug band ditties and country-western numbers.

Each player has his own strengths and interests, but the band's foundation in blues and bluegrass goes back to Thompson and Stecher's first encounter in New York City in the early 1960s. The Palo Alto-raised Thompson had already moved to Berkeley and was visiting the Big Apple, when an encounter with Stecher left them both "astonished," as Stecher put it.

"We'd been listening to similar things and played very similarly," he recalled. "In each of our little worlds, we were the only ones who played that way. Our styles have diverged some, but doggone it, we know what the other is going to do."

Stecher and Thompson ended up starting the Asphalt Mountain Jungle Boys with Jerry Garcia in the mid-'60s, and by 1968, Stecher had taken up permanent residence in the Bay Area (he now lives in San Francisco). Nygaard, who lives in Fairfax, arrived in the Bay Area in the mid-1980s, and before long, started accompanying Thompson on rhythm guitar.

While Thompson plays in half a dozen different bands with his wife, fiddle, vocalist, guitarist and accordionist Suzy Thompson, Stecher has more time these days since coming off a five-year run with Peter Rowan. And Nygaard is slowly returning to the performance circuit after many years working as an editor at Acoustic Guitar magazine.

They don't come together for Guitars Without Borders often, and each concert seems to multiply the musical possibilities. Ultimately, what sparks the creative frisson in the trio flows as much from their differences as from their shared musical interests.

"Scott's a little younger, and he has more jazz influence," Stecher says. "I've played North Indian classical for a very long time and some Middle Eastern music. I love listening to Eric and Scott, because they've heard stuff I haven't I heard."

Contact Andrew Gilbert at jazzscribe@aol.com

GUITARS WITHOUT BORDERS

When: 2 p.m. Sunday
Where: Mighty Fine Guitars, 85 Lafayette Circle, Lafayette
Tickets: $15-$20,
925-268-8226,
www.mightyfineguitars.com