The Ark, sponsor of the annual Ann Arbor Folk Festival, today announces the headline acts for the 34th edition of its signature fundraiser, and both are popular with local audiences: the Avett Brothers and the Swell Season.

As has become the norm in recent years, the festival will take place over two nights, Friday, January 28 and Saturday, January 29, 2011, at the University of Michigan's Hill Auditorium. The show starts at 6:30 p.m. both nights. The Avett Brothers will headline Friday, generally the night that skews a bit toward edgier performers and a younger audience. The Swell Season — the duo of Glen Hansard and Marketa Irglova, best known from the movie "Once" — anchor Saturday's somewhat more tradition-oriented lineup.

Additional performers will be announced soon. (A typical night at the Folk Festival features seven or eight acts.)

Tickets go on sale first to Ark members and those buying premium seats. There is then a student presale, then the general sale.

Ark members will have a chance to buy tickets in a mail-only presale Nov. 1-30. Tickets are $47.50 for one night or $85 for both. For information on becoming an Ark member, call 734-761-1800.

"Gold Circle" and "Platinum Circle" tickets — the best seats in the house — are on sale from Nov. 1 until they are gone. They are available by phone at 734-761-1800 or by mail. Gold Circle tickets are $80 for a single night and $135 for both. Platinum Circle tickets are $160 for a single night and $270 for series tickets. Gold and Platinum Circle tickets include a tax-deductible donation to The Ark. Platinum Circle tickets include backstage passes during intermission and an invitation to a Saturday pre-glow party.

Students can purchase tickets in advance of the general public, Nov. 15-20 through the Michigan Union Ticket Office in person only with a valid student ID. Student tickets are priced at $30 and $47.50 for a single night or $50 and $85 for both nights.

Tickets go on sale to the general public on December 1 by phone at 734-763-TKTS or in person at the Michigan Union Ticket Office, Herb David Guitar Studio, the Ark box office, or any TicketMaster outlet, or online at Ticketmaster.com. General public tickets are $30 and $47.50 for a single night; $50 and $85 for both. The Ark's description of the Avett Brothers: "Like so many great American bands, North Carolina's Avett Brothers are hard to classify musically. In the words of the Atlanta Journal-Constitution, they're 'a band that exploits the tensions between the rustic Old South and the cosmopolitan New South, between rootsy bluegrass and rowdy punk rock, between reverence and irreverence.' The brothers shift from quiet balladry to power chords, sometimes within the same song. And their mix of styles is not a gimmick or novelty but comes out of a deep-seated drive to encompass all the impulses of Southern music and American music — sentiment, tradition, transgression, transcendent intensity. The Avett Brothers recently teamed up with legendary producer Rick Rubin (Tom Petty, Johnny Cash) and released the gorgeous album 'I and Love and You,' and their Friday-night headliner appearance at the 2011 Ann Arbor Folk Festival comes just as they seem to be on the cusp of breaking through to superstardom." Listen to the Avett Brothers "Shame" from "Live, Vol. 3" (MP3).

The Ark's description of The Swell Season: "The Swell Season is the duo of Glen Hansard, frontman of the Irish rock band the Frames, and classically trained singer and songwriter Markéta Irglová. She's Czech, and the duo's name comes from a novel by Josef Skvorecky. The two appeared in the terrific Irish indie film 'Once,' with completely real-life performances as struggling Dublin musicians, and they won an Academy Award for the hit 'Falling Slowly' from the film's soundtrack. Hansard and Irglová fell in love themselves, brought their romantic chemistry to their fabulous duo harmonies, then fell out of love — and found that the music and the friendship were still there. In concert the Swell Season has a very rare kind of intimate appeal, with a depth that seems to arise out of the profound complicatedness of human romantic relationships." Listen to the Swell Season "Young Hearts Run Free" (MP3).

The Ark — Ann Arbor's nonprofit home for acoustic, roots and world music — sponsors the festival along with U-M's University Unions Arts & Programs.