All right, pop quiz. When you think of American music, what comes to mind? If you answered Britney Spears or Dick Clark, then you should stop reading now, because there’s plenty of good American music in “Down From The Mountain,” but it won’t be coming to an MTV near you. Instead, you’ll find a bit of bluegrass, some blues and a little gospel thrown in for good measure.

“Down From The Mountain” documents a benefit concert performed by the artists on the soundtrack of the Coen Brothers’ “O Brother, Where Art Thou?” and features songs both from and inspired by the movie. As if the music weren’t enough, the co-directors of “Down From The Mountain,” Nick Doob, Chris Hegedus and D.A. Pennebaker, built their reputation on musical films like “Ziggy Stardust and the Spiders from Mars” and “Depeche Mode 101.” Pure talent.

Only one word can describe the footage and the music: unaffected. Both the backstage and the performance scenes come off in the humblest of manners, from the deadpan charm of the MC John Hartford (who passed away in June) to the nervous and infectiously cute Peasall sisters asking which mic to go to as they walk on stage. Even the behind-the-scenes footage looks like it was captured on a camcorder, adding to the deliberate lack of pretenses in the film.

If you liked the “O Brother” soundtrack, you’ll definitely appreciate the performances in “Down From The Mountain,” especially the eerie a cappella rendition of “(Didn’t Leave) Nobody But The Baby” and Alison Krauss’ performance of “Down To The River To Pray.” Even if you didn’t care for “O Brother,” you can still get a kick out of David Rawlings’ priceless facial expressions as he hits those high notes, without forsaking your hatred of country music.

“Down From The Mountain” is showing tonight at 7:30 in Campbell Hall, presented by Arts & Lectures.