As Ambassadors, Masters Paint in Pure Blues : Folk music: The acoustic guitar-and-harmonica duo of John Cephas and Phil Wiggins taps into the style’s roots.

Mention “the blues” to contemporary music fans, and they’ll most likely get images of the macho, electric-blues guitarist or the swaggering harp player cranking up the volume, bending the notes and singing in a gravel-gargled voice about cheap hooch and two-timing women.

Frequently lost among these modern cliches is the blues’ quieter, more dignified origins as a rural, tradition-based music, drawing from African and European sources to form perhaps the quintessential American music idiom.

This side of the blues is exemplified by the delicate musical excellence of a Mississippi John Hurt, the primal intensity of a Charlie Patton, the tempered wisdom of a Huddie Ledbetter.

John Cephas and Phil Wiggins, who perform tonight at the San Juan Capistrano Regional Library, are among the few modern acts to carry on the early legacy of the folk blues.

The acoustic guitar-and-harmonica duo specializes in a style known as Piedmont blues, a musical approach and regional sound born of the Southeast, stretching from Richmond, Va., to Atlanta.

It embodies a difficult, intricate style of guitar playing that embraces the backwoods sound of the Mississippi Delta region, yet also echoes the more urban, sophisticated strains of ragtime.

During a recent phone interview from his rural Virginia home, guitarist Cephas discussed some of his early heroes of the Piedmont tradition. When Cephas tells a story in his down-home regional accent, his tone captivates.

“Blind Boy Fuller was probably my main influence, and then Rev. Gary Davis,” he said. “Rev. Gary Davis, in his later life, played a lot of spirituals, but the technique he used held true to the blues. He was really fantastic, very complex.

“He played all kinds of stuff--ragtime, basic blues. Blind Blake was another one that was pretty complex. Oh boy, a lot of guys couldn’t catch him at all. He played all that ragtime stuff--I’m telling you, it sounded like he had 10 fingers on each hand. Yeah. Uhhhh-huh.”

*

Cephas, 64, is something of an ambassador for old-time blues. Along with Wiggins, he’s toured the world, emphasizing colleges, universities and community centers in lieu of bars and nightclubs. They’ve held a number of teaching residencies, won a wall full of honorariums, appeared on stage, radio and television and recorded seven albums for a variety of small blues labels.

While Chicago-style electric blues has enjoyed a remarkable surge in popularity and visibility in the past decade or so via such performers as Stevie Ray Vaughan, Robert Cray and Buddy Guy, Cephas says he views their brand of music as simple and artless.

*

He draws a sharp line between their commercial posturing and the unpretentious music he performs. If he sounds a bit self-righteous, his elitism is at least informed by a keen sense of history.

“I’m just not into the Chicago style of playing blues,” he said. “There’s already enough musicians out there playing that stuff. A lot of guys would rather just pick up a flat-pick and play electric guitar rather than learn the intricate technique of finger-picking songs. That’s because it’s so hard. Yeah, uhhh-huh. It’s hard to get that coordination between your fingers, hand, guitar and voice. I teach it around the country. It’s not easy at all. And (Chicago blues) doesn’t have any historical value to it, either.

“The stuff we play is the grass roots, the beginning of almost every kind of music you hear today. People forget about that, forget about where the music actually came from. I take a kind of pride in playing this style, keeping it alive and making people aware of what contributions it made not only to America, but all over the world.”

Cephas met Wiggins, whose harp-playing is influenced by Sonny Terry, at the American Folk Life Festival in 1976.

“I was playing in a duo with a piano player from Birmingham, Big Chief Ellis,” he recalled. “Phil was playing with a street singer from D.C., Flora Molton. Chief and I, we heard Phil, and he was playing such wonderful harp that we conspired to get Phil to join with us.”

*

When Ellis died in 1979, Cephas and Wiggins continued as a duo and have been working steadily on the road ever since, happily spreading the word and showing no signs of slowing.

“I’m a bachelor, and I don’t mind being on the road,” Cephas said. “I’ve been doing this so long now, I don’t really see anything else I want to do. Sometimes I like to get home and work on my garden, but after a while, it’s time to go play music again.

“Yeah, uhhhh-huh.”

* Cephas and Wiggins appear tonight in La Sala Auditorium at the San Juan Capistrano Regional Library, 31495 El Camino Real, San Juan Capistrano. Show times: 7 and 9 p.m. $5, adults; $3, children. (714) 493-1752. Hear Cephas and Wiggins

* To hear a sample of the album “Bluesmen,” call TimesLine at 808-8463 and press *5560.

Details on Times electronic services, B4