Joe Wilson, executive director of the National Council for the Traditional Arts that produces the National Folk Festival, has a story he likes to tell about the time more than 50 years ago when he first saw legendary folk guitarist Doc Watson playing music on the street in Boone, N.C. Wilson had been out picking beans all day and had come into town to spend his earnings – 50 cents. He happened upon Watson playing the guitar.

“I was watching Doc and the music was so good, I gave him a quarter,” said Wilson. “I had to save the second quarter to get home. But I watched for another 45 minutes or so and then gave Doc the other quarter and hitchhiked home.”

These days, Wilson produces festivals that feature Watson and others who play American roots music, as well as traditional music from other parts of the world. He’ll tell you that the real absolutes in music are that a performer is in tune, in time and hits the note. But, when it’s folk music, there’s also the issue of authenticity. Which begs the question: Once you move Doc Watson off the street and onto the stage, is the authenticity endangered?

“Certainly, something is different about the music when you move it,” said John Michael Vlach, who teaches American studies and anthropology at George Washington University in Washington, D.C. “Certain things don’t carry well on a big stage. Some ritual-based phenomena are not to be broadcast. Or they end up being sanitized. But the guys who can actually make that move are the ones who are ready. They’ve played to everyone in town or in the village, and they want a bigger audience. When they get to that moment and hit their stride, they are mentally back in Afghanistan or Texas or Montana. They bring that locality to the venue and, for those in the audience who are willing to go, they are in that locality as well. It’s a profound psychological exchange.”

Watson is not on the lineup at this year’s festival in Bangor, but Mamadou Diabate is. He plays the kora, a harplike instrument made out of a calabash gourd. He learned the instrument from his father back in Mali, Africa. While the music was meant for ceremonial purposes, Diabate’s father sent him to the city to seek out the influence of other practiced players.

Diabate described the exchange between artist and audience in one word: jeli. In Mandingo, it means musician-storyteller.

“We connect people,” said Diabate. Underscoring Vlach’s point, he added: “I feel the kora doesn’t lose value because I am not playing it at a ceremony. I feel it’s more connected because it’s new for people. I have the same feelings and I am playing the same kind of music as a ceremony. I’m giving an idea of where I came from and these are the good things about my culture.”

As with Diabate, many of the performers at this year’s National Folk Festival consider themselves emissaries who transport music from its place of origin: a village in Africa, the mountains of Appalachia, the streets of New Orleans, a farm in Korea and the islands of Nova Scotia. They concur generally that something is lost, but they also realize that something is gained both in the collective experience of American life and for them as individual performers.

Cindy Roy emphasized that her perception of herself as a musician was shaped not by years of lessons and a family of musicians, but by performance experience. She studied piano as a child, when her grandparents, natives of Prince Edward Island, threw dance parties with live music in her family’s home in Westbrook. But during her teen years, her interest in the traditional tunes waned and she gave up her studies. At 20, she met, Don Roy, a fiddler who would become her husband, and he encouraged her to relearn the piano to join his band.

In 1988, the Roys played at the National in Lowell, Mass., and the experience changed Cindy Roy forever. Going public at such a large event lit the fire under something that had been flickering in her for many years and bolstered her own mission to carry on the music she learned as a child.

“It took me a long time to see myself as a performer,” said Cindy Roy, who now lives, with Don, in Gorham. “When we played at the National Folk Festival, we had to wear a button that said ‘Artist.’ I was a dental hygienist and Don’s wife. But I wasn’t an artist. But after the festival, where they treated us like artists, I began to see myself as an artist. And I guess I am one.”

Don Roy began playing guitar at 6 and took up the fiddle at 15. His first stage was a fiddle competition, which he won, a year later.

“Being on a stage for a competition is different because there can be tension and nervousness,” said Roy. “When you play a concert, you can free-lance and make changes.”

But the bedrock of his musical sensibility comes from private moments on the weekends when he’s not onstage and not working his job as a maintenance foreman for the Maine Turnpike Authority.

“When I am alone, I sit in a rocking chair in front of a window over the gardens,” said Roy. “I play easy, old French tunes or something a little more difficult and do variations with it. I just go with the mood. I play for a few minutes, go away, come back, do scales, tune it, put it away. But for the most part, I don’t vary what I do. What I play in my personal life is what you get onstage. But I do it to please myself first, and, if no one heard it, that would be fine with me. If people do hear it, that’s fine, too. I’m just as happy sitting in my own kitchen as I am onstage.”

For others, it’s important to have an audience.

“You need an audience,” said Wylie Gustafson, a cowboy singer and rancher in Montana. “I can sit out here and write songs and sing to my horses. But there’s a bovine and ovine indifference on a ranch. With people, there’s a whole lot of magic that can happen. The music takes people back to the campfire, out West, to the wide-open space. Our type of folk music has a way of transporting listeners to a different time and place.”

Gustafson agreed that something was lost when you took away the porch, the trail ride, the campfire, but, as with many artists, he couldn’t quite qualify what might be missing except the scenery.

Sandy Ives, director of the Maine Folklife Center at the University of Maine, said the “missing” part had to do with size. “The intimacy is lost,” he said. “In a lumber camp – as big as 80 people or smaller than that – the guys would gather around. It was a small audience, where you were a singer at one moment and part of the audience the next moment. When you put music on the stage, you’re making something out of it that it hadn’t been before. It’s that rather rough voice that you can’t duplicate onstage.” And here, Ives paused. Then he added: “You lose something but you also gain something. More people hear it and enjoy it, and that’s a gain.”

The change that happens, said Betsy Peterson, program director at the Fund for Folk Culture, an advocacy foundation in Santa Fe, N.M., should not be hastily judged as negative.

“Within the community of origin, the music may carry a totally different meaning or weight than when that music appears onstage or as a commodity divorced from its culture,” said Peterson. “That’s not necessarily a bad thing. With globalization, people are moving around easily and it’s now the nature of the beast. That’s in part how things stay new and fresh.”

For many artists, the switch from personal to public performance has to do with what Roy’s mentor uncle told him about being onstage: If you don’t have fun, don’t do it.

“Taking our music from one area to another is easier than you think because most people have some roots in this type of music,” said Linda Lay, who performs a combination of progressive bluegrass and acoustic country with Mountain Heart. As a child, she was in a family band that performed for the community. “I don’t change any at all. I have an outgoing personality and it comes across onstage. I just be myself and it seems to go well. It’s a lot of fun.”

Before the recording industry brought more roots music to the masses, hearing a yodeler from Montana or an oud player from Afghanistan was virtually impossible for most music lovers.

“First of all, unless you’re a musicologist or a crazy person like me, you’d have to ride around the country to see all these traditions, ” said Wilson. “Some people who are brought from the ‘village’ and who are put onstage find they like the stage better. And others don’t like riding around and staying in hotels. When you go onstage, you’re choosing a lifestyle. You’re not choosing an art form. Part of the psychology is that the audience members see someone they would like to be. They see someone doing something great and wonderful and they want to be like that. For those of us who want to get a look at all the riches around the world, I’m thankful there are people who make those choices and feed the audience.”