AS A GLIMPSE of folk-music-obsessed Greenwich Village in the late 1950s and early '60s, "Inside Llewyn Davis" has its gritty, fleeting charms.

And if the film gets people digging for discs by the late, great Dave Van Ronk, upon whom the title character is very loosely based, all the better.

But as friends and fans will attest, the real Dave Van Ronk never stands up in the movie.

Leading the boo-brigade is New York-based singer/songwriter Christine Lavin, a pal of the real deal and still the gracious mother hen of the urban folk/singer-songwriter scene.

"I don't understand how such a larger-than-life character like Dave Van Ronk, who wrote a wonderful book [The Mayor of MacDougal Street] filled with hilarious stories could inspire such a joyless, limp, pointless film," Lavin shared earlier this week. "Llewyn Davis is the antithesis of Dave Van Ronk."

Even if you just observed him as this "kid" did when Van Ronk played here at the Second Fret and Main Point coffee houses, you were struck by this towering inferno's gregarious nature and uncommon, one-man-folk-festival aesthetic. So generous of spirit, so eclectically ahead of his time when almost everybody else in folk was still playing at being "purist," digging themselves deep into a niche.

While not much of a songwriter, Van Ronk, who died in 2002, had an amazing knack for finding, reworking and merging all kinds of interesting songs - hearty sea shanties (he spent time in the Merchant Marines), creepy old English ballads as collected by Francis Child, daffy children's ditties, lotsa uptown ragtime riffers and earthy southern blues, plus the occasional contemporary folk-pop number dropped by the young chickens Van Ronk took under his wing, like Tom Paxton, Bob Dylan and maiden-in-waiting Joni Mitchell.

"Inside Llewyn Davis" depicts a hopeless, homeless loser who crashes on others' couches. In real life, it was Bob Dylan who slept on Van Ronk's couch.

Right artist, wrong album

In one of the saddest ironies we've ever encountered, Concord Records has just reissued the wrong album by the man - the original, 12-track edition of "Inside Dave Van Ronk." You can easily imagine how that happened.

The label should have put out his landmark prior set, "Dave Van Ronk, Folksinger," which inspired a gazillion contrapuntal guitar pickers and from whence sprang two of the most important songs covered in the film. It's currently out of print, unavailable on CD or vinyl. But hey, you can always buy a digital download.

Recorded during the same 1962 sessions as "Inside," and merged with the other for a while in a two-disc reissue, "Folksinger" was the set that assured many a white boy it was OK to howl, growl and whisper the blues. Van Ronk - New York born, of Dutch/Irish roots - did so with blood-vessel-bursting force and subtle conviction, sounding so much older, wiser and wearier than his (then 26) years.

Among its many priceless gems is the ironically funny, death-is-boring-themed "Hang Me, Oh Hang Me," which the Coen brothers have Llewyn Davis perform in the opening moments of their film.

"Folksinger" also gave birth to Van Ronk's signature treatment of "Cocaine Blues," another example of his so-bad-it's-good, laughing at adversity nature.

"Cocaine's for horses, not for men. They tell me it'll kill me, but they don't say when," he sang with an unmistakable cackle.

That song is also acknowledged in the Coens' film, and surely you've heard Van Ronk's complete version, though probably not in his voice. Jackson Browne did a knock-off so perfect (and popular) he should have been sued for plagiarism.

But that wasn't Van Ronk's nature.

A not-so-serious man

On his first Columbia album in 1962, Dylan copped Van Ronk's treatment of "House of the Rising Sun." With no complaint from the "Mayor."

Another case could have gone to court after Van Ronk turned down Chicago club owner/talent manager Albert Grossman's offer to participate in a modern folk trio. The group came out as Peter (not Dave), Paul and Mary and won special cheers for a rouser called "If I Had My Way" that was the spitting image of Van Ronk's "Samson and Delilah" on "Folksinger."

"People refer to gatekeepers, and Dave Van Ronk was one of those guys," said Jeff Place, producer and essayist for Smithsonian Folkways' new, three-CD Van Ronk retrospective, "Down in Washington Square." "He did the research and nurtured a lot of people onto the repertoire, people who went on to record those songs and become better-known than he was."

Van Ronk didn't fall off the edge of the Earth, though, as Davis seems to in the Coens' film. He kept on performing and making albums, at least 18, though none would ever have quite the same cultural impact as "Folksinger."

Lavin says Van Ronk never gave up the hustle.

"One of his schemes he hoped would get him rich was the hangover cookbook. Foods that not only can you tolerate when you are desperately hungover, but foods that hasten the end of that awful hangover. Another of his schemes: exporting Toni Home Permanents to China. 'Imagine,' Dave liked to say, 'a billion people with straight hair ... ' Can you imagine Llewyn Davis trying to get these ideas off the ground? Nope. What a waste.

"The Coens are crafty," Lavin concluded. "Their film looks good, sounds good, but it's a beautiful frame around a faded, out-of-focus Polaroid, when it could have been so much more. You know, Truman Capote got two bio-pics a few years ago. I hope someone else will take Dave's book and make the film these boys failed to make. But that's just me."

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