Music: The Beat goes on with Jay Farrar and Ben Gibbard

They met for the first time the night before the sessions began. Even after they started, Jay Farrar remembered, "We didn't really know what we'd wind up with."

To top it off, the Son Volt frontman said, "Our working relationship was forged by the almost absurd circumstance of having cameras rolling on us by Day 2."

It was against quite a few odds, then, that Farrar and Death Cab for Cutie singer Ben Gibbard transformed a request to write "a couple songs" for a Jack Kerouac documentary into an entire album based on the writer's midlife novel "Big Sur."

Titled "One Fast Move or I'm Gone: Kerouac's Big Sur," the disc was issued to wide accolades in October and is the impetus for a short Farrar/Gibbard tour coming Sunday to the Varsity Theater. The songs were mostly written by Farrar using Kerouac's words, but Gibbard sings and adds his own melodic touch throughout.

"It was our mutual admiration for Kerouac that brought us together in the first place, and I think that's really what made it work as well as it did," Farrar said by phone from his home in St. Louis two weeks ago.

"We both realized this was kind of a deconstruction of the way we both worked," he said. "There was a liberating aspect in doing that. With our respective bands, normally we have to plan things out. With this, it was done on the fly, and I think there's a degree of spontaneity reflected in the recordings."

Published in 1962, five years after "On the Road," "Big Sur" uses faintly veiled fictitious characters to chronicle his real-life retreat to a cabin on the scenic coastline south of San Francisco -- partly to escape the limelight, and partly to sober up. It's a gritty, somewhat maniacal novel that foreshadowed the writer's alcohol-hastened death at age 47.

Ever since he dissolved the original lineup of Son Volt in 1999, Farrar has maintained an adventurous streak. He recorded a string of experimental EPs and albums under his own moniker as well as the one-off name Gob Iron, plus he scored the small indie movie "The Slaughter Rule."

The "One Fast Move" shows have been a welcome diversion. Son Volt's Mark Spencer, Death Cab's Nick Harmer and Superchunk's Jon Wurster make up the backing band. The tour was split between the fall and winter to fit around Gibbard's Dec. 28 wedding to Zooey Deschanel.

"It was taken into consideration," Farrar said wryly, letting out a rare laugh.

As for his shotgun-wedding-like partnership with Gibbard, it looks as if it will end in Minneapolis. At least for now.

"I think we're definitely both open to something else occurring after this. But we'll see what happens on down the road."