"What's up, Cajuns?" ask the youthful innovators of Louisiana's Feufollet, performing Sept. 12 at the Eagles Hall. "What's up, Cajuns?" went from inside joke to habit for the band members whose love of roots music began in the cradle. Their latest album, Cow Island Hop (Valcour Records; July 2008), brings Mellotron to melancholy ballads, funky horns to time-tested fiddle tunes, and a cool new energy to Cajun music.

A lot of feeling lies behind this little salutation: the irony of singing French songs in an Anglophone land, of young hip players devoted to old traditions, of iPod-age eclectics dedicated to a very localized ethnic culture. Emerging from a generation newly engaged with their once-threatened Francophone heritage, Feufollet has Cajun music in their blood. The mostly 20-somethings grew up speaking French, bopping at Cajun jam sessions as toddlers, taking music lessons from older musicians who put Cajun music on the map, and later touring the U.S. as precocious young performers.

"A lot of people today are more self-consciously Cajun, but in a good way," Feufollet accordionist and fiddler Chris Stafford explains. "Our group and our generation are really discovering who we are and where we came from."

This discovery started early. Feufollet's fiddler, Chris Segura, remembers his family driving back home to Cajun country, just to catch some good music: "Starting around the time I was 3, we would drive almost every weekend to Eunice, a good two hours. We'd go to the jam sessions at legendary Cajun musician Mark Savoy's record store. Or we'd go to the Liberty Theater and watch a show." Soon Segura was playing old tunes on a tiny fiddle of his own, learning from master musicians like Steve Riley.

Younger Cajuns like the musicians in Feufollet form a kind of sandwich generation, learning French and trying, along with their grandparents, to promote the language at the heart of their heritage. "The language is what's most up in the air at this point. It's up to our generation to keep it intact," Stafford muses. "There was a gap in the mid-1940s when parents didn't teach their kids French, and so a lot of the 50-year-olds don't speak it. Really old and really young people are the ones now making a conscious effort."

The one-night performance is tomorrow night at the Eagles Hall, 2305 Alameda Ave. Doors open at 8 p.m. for dance lessons; the show begins at 9 p.m. Tickets are $15; call (415) 285-6285 for more information.