It may sound like a glorious journey, but the makers of new nonfiction film "Big Easy Express" quickly learned they ranked virtually last in train hierarchy -- behind both freight and passenger cars.

Filled with musicians -- British folk rockers Mumford & Sons, Los Angeles indie-pop group Edward Sharpe & The Magnetic Zeros, and Nashville string band Old Crow Medicine Show -- their vintage railway coach was rerouted and delayed many times. Some of the bands' members were still tuning instruments as their train pulled up at depots and stopped for shows during the trip.

"I'm just shocked it all worked out," director Emmett Malloy told Reuters before the film's world premiere Saturday night at the South by Southwest (SXSW) film festival in Austin.

"It was the power of positivity, really. As cheesy as it sounds, that got the train there on time."

"Positivity" accurately describes the undercurrent of the film about the Railroad Revival Tour, an eight-day series of concerts in April 2011 that started in Oakland, California and ended in New Orleans with stops along the way in San Pedro, California; Tempe, Arizona; Marfa, Texas and Austin.

The film is sprinkled with musician interviews but it stands on the music: high-energy jams on outdoor stages in view of the trains, with Edward Sharpe & The Magnetic Zeros lead singer Alex Ebert hopping around barefoot and audiences lifting their arms in euphoria.

The bands also create American bluegrass and folk music along the way in the carpeted, living-room-like train cars with a backdrop of the scenic Pacific oceanside giving way to the southwestern U.S. desert and, finally, urban New Orleans.

What the film does not do is create gossip-fueled, reality TV-type drama. In fact, there's virtually no conflict in the film and that's the point.

"It's a hippie freakout fest that's real triumphant," said Malloy, 39, of Los Angeles, who also made a documentary about rockers the White Stripes. "At the core of it all, it's this amazing journey."

GOOD TIMES ROLL

Marcus Mumford, whose band, Mumford & Sons, recently played at a state dinner President Obama and first lady Michelle Obama threw for British Prime Minister David Cameron and his wife, told the SXSW premiere audience that the film captured the vibe of a trip which he called "the best thing we've ever done" -- a journey that has inspired the band's songwriting.

The filmmakers "never got in the way of the good times, and it never felt like we had to be too self-conscious," Mumford told the packed theater on Saturday. "I feel much more self-conscious now than we ever did on the train."

None of the musicians looked self-conscious when they reunited on a stage after Saturday night's SXSW premiere for a few songs, including one about not wanting to leave a train.

In a real way, their concert was a live sharing of their journey with the audience at SXSW, a music, film and technology festival that drew 300,000 people to Austin, including around 50,000 who registered for its industry conferences.

Saturday's events surrounding the movie also included an outdoor concert where teenage students from a local Austin high school marching band joined Mumford & Sons to play "The Cave," restaging a scene from the movie when the trains rolled into Austin last year.

"It felt like bathing in a ray of sunlight, even though I was up there with 80 other kids," clarinet player Haley Barlow, now a 17-year-old drum major for the Austin High School band, told Reuters about her experience.

Film director Malloy is just as enthusiastic, saying he thinks people should ride trains more often, though not to get somewhere quickly.

"After doing this, I saw that the journey through the middle of America is as spectacular as any other place in the world," he said.

(Editing by Chris Michaud and Bob Tourtellotte)

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