What is it aboutIrish music -- especially during the holidays -- that keeps listeners lining up to hear more? Eileen Ivers, the nine-time All-Ireland Fiddle Champion, contributes her own thoughts on the subject.

"I think there are a few things that really hit American audiences when they hear the music; familiarity might be one," she said, after finishing the last rehearsal before her holiday show, "An Nollaig: An Irish Christmas," taking place at the Barns at Wolf Trap on Friday. "These tunes are the fabric of our American music traditions, like bluegrass and country."

Indeed, the Celtic tradition of song and dance came to our shores with the Irish and Scottish immigrants and, along with their collaboration and integration with African rhythms, became distinctly our own.

"I think the honesty of the music is another reason," she continued. "This music is very, very joyful; the dance music, jigs and reels and the songs. Just like ornaments on a Christmas tree, the tunes in 'An Nollaig' have been lovingly passed down through the generations, as well. Some are hundreds of years old; some are new."The show highlights Ivers' clever and innovative reworkings of the familiar carols. "Hark the Herald Angels Sing," for example, is transposed into a celebratory jig, while the classic "Do You Hear What I Hear?" takes on a new life as a rousing reel. Audience participation will be encouraged for some of the tunes.

For the musical festivities, Ivers has brought along her band, Immigrant Soul, featuring singer and drummer Tommy McDonnell, button box master Buddy Connolly, acoustic guitarist Greg Anderson, and Lindsey Horner on upright and electric bass. This multitalented quartet also does double and triple duty on harmonica, whistles, keyboards and an Irish stringed instrument called the bouzouki.

In addition to the music and dancing, the group shares its particular Christmas traditions and Yuletide myths. The members even distribute tried and true family recipes to the audience.

Even as Christmas is a day that brings all Christians together in this too often secular world, Ivers is never surprised to hear grateful comments after a show.

"In the lobby, people [say], 'Thank you. You got us back to the joy of the season and what it's really about.' "