When you name your band The Autumn Defense, you're just asking to be mistaken for an emo group.

But oddly enough, in the case of this side-project from Wilco members John Stirratt and Pat Sansone, this assessment's not too far off: The slick, jazzy folk-pop is emo music for 35-year-olds, the musical equivalent of trading in tight jeans and Chucks for something more business-casual.

Indeed, The Autumn Defense set their angsty tales of lost love to well-crafted melodies and flawless production on an album designed to have a "purposefully casual tone." The music isn't so much Wilco's rebellious kid brother as Wilco's responsible older brother, who's mature enough to be taken seriously, but almost too serious to be any fun.

The songs off the duo's self-titled third album, their first since Sansone joined bassist Stirratt and the rest of Wilco as the band's designated multi-instrumentalist, were written between Wilco tour dates and honed on a nationwide tour in the winter of 2006. They'll debut for a Madison crowd tomorrow night at the Café Montmartre.

"Canyon Arrow" starts the collection of mellow tunes off promisingly with a hybrid mix of bossa nova grooves, drifting folk harmonies and a jazz flute part that would do Ron Burgundy proud. The pair jump seamlessly between seemingly disparate sections of fingerpicked guitar asides and tight Latin grooves, driven by a skipping bass line and a vocal pairing of baritone and falsetto parts. It's as slick as a Steely Dan record, but just when you begin to tire of the smooth-jazz schmaltz, a surprisingly moody bridge breaks things down with a deftly bowed cello part.

The Autumn Defense turn to this time-honored formula time and again on the album, setting out to do well-structured pop and doing it well, rather than taking any exorbitant risks.

To accomplish their ends, Sansone and Stirratt look to the past, taking pages from the songbooks of similarly minded groups. The duo's admitted Simon & Garfunkel influence comes through on the distant harmonies of "Where You Are," which enter and exit the frame like traffic on a far-off freeway. Unlike its wet rag of a title would imply, the song pulls off the kind of earnest, romantic philosophizing its predecessors did so well.

"Simple Explanation," on the other hand, captures only the rich suburbanite-pretensions of tunes like Simon & Garfunkel's "The Dangling Conversation," ruining its overly clever lyrical theme with a few too many two-dollar words.

In fact, the pair has an ear for clunker lyrics, spewing out too many condescending lines — "You could have any other/ and don't tell me I'm wrong" — and pointless relationship musings to match their musical strides.

The vocals are also hit-or-miss, with quavering, quasi-vibrato keening either coming off as potently emotional or too soft-rock sappy for their own good. On "Winterlight," the lead part sounds as pure and naive as a particularly clueless schoolboy, but its dreamy evenness immediately relegates the song to the rear of the listener's consciousness. As a result, the song fails to make much of an impression besides the vague feeling you've heard the melody before in some Guster tune.

But on "Feel You Now," the band shows remarkable skill in lulling the listener into a warm-and-fuzzy complacency before the vocals take off on the first of many flights into more soulful territory, complete with the swooping strings on the bridge that surely must have been lifted from an Al Green record.

The Autumn Defense are at their best when they focus on the influences that obviously inspired this album. "Estate Remains" succeeds when Stirratt and Sansone give free reign to their Beatles inspiration, unleashing an "Eleanor Rigby"-esque string section on the chorus that chunks along like an old jalopy. Meanwhile, an increasingly audible "Lucy in the Sky with Diamonds" harpsichord dances overtop in a display of pitch-perfect musical restraint.

Throughout the album, the group effortlessly attains the kind of polished sound that comes from years of steady gigs. In fact, at points it's almost too polished: A little rough-around-the-edges realism would have been a welcome break from the gentle babble of the musical brook that has sprung up from the Wilco sidemen's untapped creativity.

While it's not entirely fair to judge the duo completely by their Wilco affiliation, the music is nowhere near as edgy or exciting as Wilco's unique blend of noise- and folk-rock. For all The Autumn Defense's mellow, good-natured songcraft, it would have been more endearing to hear a few echoes of the shambling, beautiful mess Wilco creates so adeptly.

The Autumn Defense is the kind of music you might want to play before a dinner party — it's restrained, slightly innocuous and sounds just as good at 60 decibels as it does with the volume cranked. And as long as nobody's listening to the grown-up emo-kid lyrics, it sets the mood perfectly.

The Autumn Defense will play the Café Montmartre Thursday at 9 p.m. Tickets are $13 in advance and $15 on the day of the show.

Grade: 2.5 out of 5