After a hiatus spanning more than two decades, guitarist James “Blood” Ulmer’s Odyssey trio has returned with a new album, a 55-minute tour de force that neatly encapsulates the myriad musical directions that its iconoclastic leader has pursued over the past half-century. Don’t let the CD’s title fool you: An amalgam of free jazz, country-blues, psychedelic rock, slippery soul, and sanctified funk, Back in Time is no step backward, even though it does mark the first time that Ulmer has recorded with violinist Charles Burnham and drummer Warren Benbow since 1983, when the three men recorded the widely praised but commercially disappointing Odyssey LP for the Columbia label. Integrating basically every offshoot of the African-American musical vernacular and creating a kind of universal language from the various dialects, Back in Time is ultimately as remarkable as its creator, who, if you ask me, deserves his own section in the record store, if not his own franchise. But that’s just wishful thinking, of course. He might be the most important outside-jazz guitarist in history, the natural heir of Jimi Hendrix, a technical innovator and a sui generis genius, but, chances are, your run-of-the-mill Trey Anastasio fan has never heard of Ulmer and therefore has no idea what distinguishes a prodigious noodler from an actual prodigy. Given Ulmer’s undeserved obscurity, a bit of background history is in order. He grew up in segregated South Carolina, the gospel-steeped product of a strict Baptist upbringing in which all forms of secular music were considered the work of the devil. After migrating north, as did so many black musicians of his era, he spent most of the ’60s playing in funk bands. In the early ’70s, he moved to New York City and began his career as a jazz musician, performing with the likes of Art Blakey and Rashied Ali. By 1973, he’d begun playing with free-jazz icon Ornette Coleman, whose “harmolodic” theory of improvisation, in which harmony, melody, and rhythm receive equal compositional weight, was a lasting influence on the young guitarist. After winning over experimental-rock fans in the ’80s with an album for Rough Trade and sharing bills with underground darlings such as Public Image and Captain Beefheart, Ulmer embraced more conventionally structured idioms. He’s spent much of the new decade immersing himself in the blues, recording a handful of singular vocal-oriented albums, including his first solo venture, Birthright (Hyena), which was chosen by DownBeat readers as 2005’s Blues Album of the Year. Back in Time is both a reminder of Ulmer’s avant-garde heyday and a recapitulation of his more recent Delta-blues-inspired output. From the spiritualized jazz of “Last One” to the echoing fugue of “Channel One” and the salacious straight-ahead blues of “Let’s Get Married,” the 12 tracks draw on seemingly disparate sources to reveal unexpected tonal commonalities. Odyssey also revisits compositions from Ulmer’s back catalog — including his brilliant signature song, “Little Red House” (from Are You Glad to Be in America? ), and the propulsive “Woman Coming” (from his Coleman-produced debut, Tales of Captain Black ) — and transforms them, sometimes to startling effect. Burnham’s violin careers from lyrical to lacerating, its sound rendered nearly unrecognizable in places by a wah-wah pedal; Ulmer’s trademark staccato attacks morph into searing hard-rock leads and languid rhythmic textures; Benbow’s funky undercurrents percolate for awhile before erupting in bright cymbal crashes. Music this far-reaching and abstruse could easily devolve into chaos, but the trio always manages to retain its visceral force, to ground itself in familiar forms while gesturing toward the stratosphere.