Music fans gathered Saturday in Sebastopol to revel in tunes and a fellowship that aficionados say is particular to bluegrass and folk music.

About 400 people turned up for the 14th annual Sonoma County Bluegrass & Folk Festival at the Sebastopol Community Center, where audience members were encouraged to "bring your instrument to jam" and participate in workshops during the eight-hour event.

"It's a living, breathing, growing art form," event director Mark Hogan said.

And playing it keeps it alive, he said.

While fans raved about the lineup of performers who were scheduled to play Saturday, including Missy Raines & The New Hip; Front Country; Rita Hosking and Cousin Jack; and High Country, many said it was the impromptu, audience-driven jam sessions that make the annual event special.

"There is something really special about going into a group of strangers and playing," said Steve Gilford, a 50-year veteran of the autoharp and volunteer at Saturday's event.

A jam has its own chemistry, he said.

"You start realizing that you are breathing in sync, you body is moving in sync, your physiology is in sync, and this is all happening within minutes," he said. "My feeling is it's always better to play music than to hear other musicians play it, and this allows you to do both."

Hide Mizuno traveled from San Francisco do a bit of both. A fiddle player, Mizuno played with fellow musicians outside before heading back in to listen to the Mike Justis Band.

"At first, I make sure of the skill level and if I'm not totally out of range. If I feel comfortable, I squeeze in," he said. "If they are very advanced, I just listen."

"There are many ways to enjoy this music, but the best way is to play," he said.

The festival is a joint production of the Sonoma County Folk Society and the California Bluegrass Association.

Bruno Brandli of the California Bluegrass Association said the event has sought to draw in younger musicians and fans as a way to keep the music alive. The jam sessions and workshops are aimed at all levels of musicians.

"If we don't bring more young people to this music, it's going to die out," he said.

For Loraine Nichols, a Petaluma resident who spent more than three decades living in South Carolina immersed in bluegrass music, events like Saturday's festival are nourishing to both her musical needs and her desire for community.

"This is the best way to hear it," she said, after stepping out of a jam session in which she sang "There's No Hiding Place Down Here," by the Carter Family.

"All the people are in touch with one another ... and because they are in touch with each other, the audience is in touch with you."

(Staff Writer Kerry Benefield can be reached at 526-8671, or on Twitter @benefield.)