You’ve heard Jon Brion, whether you know it or not. Jon Brion, producer: Aimee Mann, Fiona Apple, Rhett Miller, Rufus Wainwright. Jon Brion, instrumentalist: Jellyfish, Elliott Smith, eels, Macy Gray, the Wallflowers, the Chemical Brothers. Jon Brion, composer: Hard Eight, Magnolia, Punch-Drunk Love. Jon Brion, It-boy: The New York Times, LA Weekly, The Onion. If one of those things hasn’t crossed your pop radar in the last six years, you’re either deaf, dumb, blind, or an enemy of art. Otherwise, you’ve heard Jon Brion.

So we’re clear on that, I hope. But we can shelve those stunning accomplishments for a moment and really look at Jon Brion. "Superstar producer" status aside, he is a one-man orchestra, a mad scientist, a boffo songwriter, and very possibly the last great tonal alchemist. Sure, he may be the most dynamic and gifted producer working— a worthy heir to masterminds like George Martin and Brian Wilson, the two artists to whom he is most often compared— but there is, as it were, Another Side of Jon Brion, a side often discussed but rarely investigated. This is the side that has, for the last seven years, hosted Genius Pop’s wake every Friday night at Largo in Los Angeles. This is the side whose stunning freshman effort, Meaningless, contains some of the most exciting pure "pop" (or, as he’s called it, "unpopular pop") writing since Lindsay Buckingham’s immortal Tusk songs. This is the side that, every Friday night, guts the Canon with a taxidermist’s precision, creating ugly-pretty creatures like the lounge piano "Anarchy in the UK" and the harmonium-only "Maybe I’m Amazed."

Brion’s legendary Friday night show at Largo is something of a latter-day Ark of the Covenant for music connoisseurs. Facetiously billed by club owner/manager Mark Flanagan as "Wee Jon Brion," he creates from his laboratory on stage— two guitars (one acoustic, one electric), octave pedal, drum kit, synthesizers, upright piano, children’s toy piano, sampler— a sound so strong and imposing that it defies traditional pop logic.

To my thinking, this is the stuff of great pop music— variation, excitement, raw talent, and exacting craft meeting at the crossroads of a really good two-to-five-minute song. It’s strange, then, that Jon’s music— his "unpopular pop"— is just that: wildly unpopular. His debut record, Meaningless, shelved by Atlantic, has sold a meager few thousand copies on cdbaby.com, and his work on Paul Thomas Anderson’s Punch-Drunk Love, despite being one of the most exciting film scores ever to grace the screen, was completely overlooked by the Academy when Oscar time rolled around. Fiona Apple’s When the Pawn…, a record even Ms. Apple realizes should’ve been billed as a Jon Brion/Fiona Apple album, sold three-and-a-half-million units less than her wildly popular Tidal, a record that pales in comparison. In a Los Angeles music scene that, in terms of songwriting, eclipses anything happening in the East, Brion is both muse and jinx: It seems that any album he really puts his heart into is destined to forever skirt the edges of the mainstream.

Listening to Meaningless, this scenario is almost unimaginable. The songs— like "I Believe She’s Lying," a breakbeat-and-acoustic-guitar slamdance of paramour’s paranoia, and "Ruin My Day," with its almost Motown rhythms and gorgeous strings— are so catchy that they verge on becoming intolerably perfect. You want so badly for these tunes to show up in Top 40 rotation, to be played to the point of intolerability like Eminem’s "Lose Yourself," Weezer’s "Buddy Holly," or Fountains of Wayne’s "Stacy’s Mom." How can music this finely hued— these ingeniously complicated "pocket symphonies" in the tradition of the Beach Boys’ "Good Vibrations" and the Beatles’ "We Can Work It Out"— be so ignored?

A large part of it might be Jon’s image. A geek in his late thirties who wears bright red suits and proudly displays a crate-digger’s passion for pop minutiae, he doesn’t exactly fit in with the youth-obsessed Top 40 clique. The genre Brion would be MTV’d into, if he were to have a major release, would no doubt be that of "New Singer-Songwriter," a cabal that includes such under-talents as John Mayer, Jason Mraz, Damien Rice, Vanessa Carlton, Sarah McLaughlin, and Ryan Adams. The music these artists are creating is watered-down Brion— the same classic song structures, even (at times) the same vocal intonations, without the lyrical punch or melodic complexity.

His inability to "break through" may also stem from a distinct drift away from the classical in the mainstream. Sounds that were wildly experimental a mere twenty years ago— spacey Eno synths and quirky Kraftwerk blips that never had a chance of Top 40 acceptance— have become par for the course in modern music. The recent Britney Spears single "Me Against the Music" is jam-packed with weird oohs and aahs, tweaked-out machines, and intense beats that would never have made it in the heyday of Paul McCartney and Smokey Robinson. Beck’s genre-defying mix of West Coast hip-hop, Byrds-like folk, and avant-rock experimentation is as far out as Can or Lou Reed’s Metal Machine Music… and yet Odelay went platinum more times than Jagger and Bowie skittered away for tête-à-têtes in the basement of Studio 54. Andre 3000 of OutKast pushes the boundaries of hip-hop past anything Paul’s Boutique could’ve predicted, mixing Prince with Pendergrass with Zappa with God knows what else. As the mainstream moves further towards these "avant-pop" experiments, music like Brion’s becomes increasingly irrelevant. Who, after all, wants to hear piano, drum, bass guitar, and mild synth when Radiohead stacks fifty different beat-boxes and blip-makers on one track?

The case for mainstream acceptance would be harder to make if Brion were in line with the more esoteric "unpopular pop" groups playing the underground right now, groups who gleefully mix psychedelia with a Tin Pan Alley ethos and a head full of brown acid. Groups like Of Montreal (the aforementioned Tin Pan Alley–meets– Firesign Theatre), Neutral Milk Hotel (fuzz-box White Album–era Beatles meets John Cale), and the Coral (the Doors, Stephen Stills, the Kinks, and the Specials in a Gothic gang-bang) are kept from the pop charts by their do-or-die indie aesthetics and devotion to genuinely weird experimentation. As songwriters, none of them can touch Brion’s bell-bottom cuffs, and none of them have the ability to write melodies that are as instantly memorable. Jon, with his old-fashioned musical weltanschauung and mild manner, is right in the middle of these two worlds, much like his tragic friend Elliott Smith. Rejected by the underground as "too poppy," shunned almost entirely by the mainstream, artists like these are damned to a life of cult followings and critical acclaim— two things that must mean very little to people who, since they were young, have wanted nothing more than to sing and write songs people want to hear.