Ollabelle was stopped cold. Sitting in a recording studio, the Manhattan vocal group, whose members come from varied jazz, pop, and rock backgrounds, agonized over how to arrange "John the Revelator" for their new self-titled CD. The song is an eerie old African-American hymn, full of mystical images from the Book of Revelation: books with seven seals, burning bushes, and redemption bought with blood.
            The problem was they couldn't get Glenn Patscha's lead vocal right. It was just too clean, too pretty, too well recorded. Rustling through the studio's equipment, they found an old bullet microphone from the '60s with a lean, almost hollow sound. Still too pretty.
            So guitarist Jimi Zhivago removed the pre-amp built into the mike to prevent distortion, and -- voila! -- Patscha's voice sounded scratched and muffled, as though heard through the filters of time itself, distantly and darkly. Pounding drums and bass, screeching harmonica, organ drones, and the vocal chants of Amy Helm and Fiona McBain added tension and muscle. But the heart of the arrangement was the ancient mystery of the hymn itself.
            Ollabelle's approach to American traditional music is at once reverent
        and radically new, emblematic of a new folk revival movement beginning to be identified as "neo-primitivism": applying modern musical ideas to heighten the raw, authentic flavor of traditional music.
            There's nothing new about plugging folk music into the latest trends. From 17th-century chamber settings of Scottish fiddle tunes to '60s folk-rock to today's roots rock, musicians have often tried to give traditional music wider appeal by making it sound more like the fashionable music of the day.
            What's different about neo-primitive artists such as Ollabelle, Corey Harris, and Boston's Aoife O'Donovan & Crooked Still is the intent behind their fusion of old and new. Far from seeking to modernize traditional music, they use their state-of-the-art musical savvy to make the music sound even more wild, and, yes, primitive.
            "I think we all want to make music that's going to translate to people on a more basic, visceral level," says Ollabelle percussionist-singer Tony Leone, "as opposed to how most pop music is recorded these days. So much of it is done by machines that it's just not natural. We're interested in having a very human sound."
            While neo-primitivists frequently use modern recording techniques such as overdubbing, sampling, voice loops, and deliberate distortion to achieve the effect they're after, they are also integrating traditional sounds from other cultures.
            Bluesman Harris, who starred in Martin Scorsese's recent PBS blues documentary series, has been combining strains of West African music with traditional blues and even older African-American folk songs.
            On his latest CD, "Mississippi to Mali" (Rounder), he uses the calabash,
        an African gourd-like percussion instrument, on Skip James's blues classic "Cypress Grove." It puts a tick-tock tension behind Harris's sinewy guitar and haunting vocals.
            The approach is so spare and acoustic that many people don't realize how
        new this mix of instrumentation really is, which seems to please Harris. He doesn't want people thinking about what's old and new, but about what place music should have in our daily lives.
            "I'm more interested in mixing it up with musicians in the present," he says, "finding out how we can play together, and what common things we have going on as black people on both sides of the ocean. I think in America we're preoccupied with labels, and I just want to present music as something that comes out of people's real lives and cultures."
            Producer-composer T Bone Burnett may be the Quincy Jones of the neo-primitive movement. Certainly, his hit soundtrack to the film "O Brother, Where Art Thou?" brought it to a boil the way "Meet the Beatles" launched the British invasion. With a studied ear for capturing moments of raw emotion and authentic passion, Burnett recorded some of folkdom's most sophisticated artists, including Alison Krauss, Norman Blake, Emmylou Harris, and Gillian Welch, singing traditional songs that fit the 1930s Southern motif of the film.
            The commercial success and critical acclaim the soundtrack achieved gave
        artists like Ollabelle permission to embrace unabashedly the ancient aesthetics of folk tradition.
            "I think there's a reason why records like `Buena Vista Social Club' and
        `O Brother' had such an effect on people," says Patscha, "and a lot of it is that [listeners] are inundated with such processed music, stuffed full of all these strange filters."
            And yet Patscha is clearly not above using a filter or two himself, as he did on "John the Revelator." Again, what is important is the intent. Where folk rockers in the '60s tried to make folk songs sound sleek and up to date, Ollabelle wants to dirty up the sound, to make the effect even more visceral.
            But some of the first strains of neo-primitivism were heard even before
        "O Brother." In the 1999 John Travolta mystery "The General's Daughter," director Alan West used two remixes of Alan Lomax field recordings created by Bay Area composer Greg Hale Jones for a self-released 1998 CD, "Now There Is a Tree of Ghosts" (gregjones.com).
            In an e-mail interview, Jones says he was trying to create a new genre called "folktronica." For the film's theme, "She Began to Lie," he took a 1939 recording of an unaccompanied folk song, remixing it with voice loops, banjo, percussion, and sound sampling. He mixed surface noise and distortion back into the vocals to "put more of a veil between the singers and the listener."
            Within months of the film's release, however, Moby's breakthrough CD
        "Play" was released, using a similar approach of mixing archival folk recordings to electronic dance tracks, which, as Jones put it, "completely waxed my plans for fame."
            Scott Billington, a staff producer at Rounder Records, recently created
        "Tangle Eye," a potent CD of traditional music remixes. He thinks the impact of this recording approach is felt most outside the folk world, particularly among DJs and remixers.
            "The remixing process tends to put traditional music in a context that
        makes sense to people who haven't heard the raw stuff in its unadorned state."
            The neo-primitivist sound is being heard on local stages from a wave of
        young Berklee- and New England Conservatory-trained traditionalists, such as the beautifully quirky string band Aoife O'Donovan & Crooked Still, who have released a convincing debut CD, "Hop High" (Footprint).
            The inventive groove the band brings to American traditional music is fueled by cellist Rushad Eggleston, who earned a 2001 Grammy nod for his
        work on "Fiddlers Four" (Rounder). The Berklee grad says his goal is not
        to fuse the cello with traditional music but to make it feel like it's always been a folk instrument.
            "I think you have to go even deeper into the roots aspect of this music
        if you're going to be adding modern ideas to it," he says. "Because if it ends up sounding too slick, if you've got a whole bunch of Berklee influence and theory pasted on it, it's going to sound unnatural. If it doesn't have that deep, primal feeling, it just won't sound like traditional music."
            Matt Glaser, chairman of the string department at Berklee and founder of
        the bluegrass-jazz fusion band the Wayfaring Strangers, has worked closely with Eggleston. Many of these new folk musicians, he says, grew up in households where traditional music was frequently heard or played.
            "Because they grew up around this milieu, they don't see traditional music as something that needs to be validated," he says. "It's natural for them to be able to put these traditions in their own hoppers and organically come up with something new that's also sensitive to the emotional core of the music."
            So the neo-primitivist impulse may, in the end, be defined less by a desire to make the music seem old than by a fierce desire to not modernize it, as so many folk revival movements have done in the past.
            Eggleston creates a quintessential neo-primitive moment to open Crooked
        Still's sultry version of the old murder ballad "Lilly of the West." It sounds so simple it is almost primal, more like a cello sobbing than making music. But he brought all his Berklee savvy to achieving it.
            "I overdubbed three cello lines to get that effect," he says. "I had like a hot, dusty-afternoon vibe in mind, so I had the harmonic moving around, warbling a little bit. It's kind of like when you see heat from far away, and it makes everything look all wavy. That vibe just seemed to fit this harrowing tale of murder in the Old West."
       
        Originally appeared in The Boston Globe