His albums never sold that well, despite his legend. But "Biograph," a five-volume boxed set released Monday by Columbia, is proof positive that Bob Dylan remains the single most important, original and influential figure in American music over the past quarter century.

A wordscaper with the instincts of a populist musician and the skills of a poet, he has funneled his own disparate influences into a unique, eclectic vision that was nothing less than performed literature. He took command of the emerging medium of rock and invested it with messages, breaking ground for personal, social and political expression in popular music. In depicting the spirit and turmoil of the '60s, Dylan informed the conscience of his generation, and subsequent ones as well.

"Biograph," which sells for about $30, is the most comprehensive Dylan retrospective ever, spanning the 20 fertile years between his eponymous debut and 1981's "Shot of Love." Among its 53 cuts are 18 previously unreleased tracks (though they have all been circulating for years on the bootleg circuit that Dylan inspired) -- including a number of Dylan's finest songs.

Three years in the making, "Biograph" also features a 36-page booklet based on an extensive interview with Dylan -- the best thing Cameron Crowe has done in years. For hard-core Dylanologists, this interview alone is probably worth the price of the set, because it contains, for the first time, commentary on each song from Dylan himself.

Dylan's remarks are sometimes little more than brief identifications of influences or inspirations, or even mild dismissals of some of his work. (This is, after all, the man who once teased Playboy by offering to say what his songs were about, and then doing so: "Some are about four minutes, some are about five minutes and some, believe it or not, are about 11 or 12.") But, just often enough, he unwinds, and in so doing, enthralls and illuminates, even when denouncing those who scour and analyze his musical mosaics undaunted by the allusiveness, obtuseness and symbolism therein.

"Stupid and misleading jerks sometimes these interpreters are," he says, sounding a bit like Yoda. "I mean I'm always trying to stay one step ahead of myself and keep changing with the times, right? Like that's my foolish mission. How many roles can I play? Fools, they limit you to their own unimaginative mentality. They never stop to think that somebody has been exposed to experiences that they haven't been . . ."

He rejects the myth of the various "New Dylans." Unlike "what some so-called experts say, I don't constantly reinvent myself -- I was there from the beginning. I am also not any seeker or searcher of God knows what, had it all together a while back and can go any kind of way. There's nothing in any of my songs to ever imply that I'm even halfway searching for some lost gold at the end of any great mysterious rainbow-propaganda, that's all that it is . . . never have considered myself an outsider looking in, everything I do is done from the inside out, you know, I'm a mystery only to those who haven't felt the same things I have . . . "

Project producers Jeff Rosen and Bruce Dickinson have organized "Biograph" to focus not only on the various musical stages of Dylan's musical career (acoustic folk, electric rock, country gospel), but on the three overriding themes he returns to again and again: social justice, spirituality and love.

Dylan's protest songs -- from "Blowin' in the Wind" and "The Times They Are A-Changin' " to "Sen or (Tales of Yankee Power)" -- are well represented here. And his spiritual investigations form fascinating stylistic bookends (just listen to "Quinn the Eskimo" from 1967 and the gorgeous article of faith "I Believe in You" from 1979).

But it is the depth, diversity and complexity of Dylan's love songs that continue to astound. No one has been better or more honest at exploring the ever-changing landscape of personal politics, at interpreting the swirling paths of emotion or at leaving spaces for the listener to inhabit that terrain of confrontation and misunderstanding. From the sweetly sensual "Lay, Lady, Lay" to the apoplectic "It Ain't Me Babe" to the unresolved tensions of "Tangled Up in Blue" and "Just Like a Woman," the songs collected on "Biograph" reinforce this claim.

He not busy reinventing himself was always busy bending forms. As Crowe points out, before Dylan, only Elvis Presley had been able to stir up public emotions and at the same time redefine popular music. Presley did it not with substance but with attitude, and Dylan -- though never at a loss for substantive material -- connects with that approach. "It's not even the experience that counts, it's the attitude toward the experience," he argues. "I played all the folk songs with a rock and roll attitude. This is what made me different and allowed me to cut through all the mess and be heard."

"Biograph" contains enough new -- or new/old -- Dylan to qualify as a major event. Much of what's here will be familiar to the legions of fanatics who have made Dylan bootlegs a cottage industry (and who forced Columbia to release "The Basement Tapes" almost 10 years after they were recorded). But all the material has been digitally mastered and the older songs digitally remastered and put on both high-quality vinyl and chrome cassettes (the compact disc is supposed to be another quantum leap). Not surprisingly, "Biograph's" Dylan sounds terrific, his inspired, eclectic phrasing cascading into an ocean of elevated consciousness.

Among the best of the previously unreleased material is "Percy's Song," a neo-folk ballad about a miscarriage of justice that was a staple of Dylan's early repertoire (it was covered by England's Fairport Convention and for years locally by Claude Jones). "Lay Down Your Weary Tune" is a haunting paean to the beauty and power of nature (eventually recorded by the Byrds) that, some believed, represented Dylan's rejection of the protest song movement. "I'll Keep It With Mine" (an outtake from the "Another Side of Bob Dylan" sessions in 1965, with Dylan backed by piano) is an exquisite love song about the getting -- and the sharing -- of wisdom. And "Caribbean Wind" (from the "Shot of Love" sessions) is a typical Dylan tour de lyrical force, rooted in the daze between sleep and waking and "thinking about being with somebody for all the wrong reasons."

The collection boasts three rare singles: "Mixed Up Confusion" (1962), "Can You Please Crawl Out Your Window" (1965) and "The Groom's Still Waiting at the Altar" (1981). "Mixed Up Confusion" is interesting mostly as Dylan's first band session and his first foray into electric instrumentation, three years before "Highway 61 Revisited." Primitive, raucous, it's Dylan as Little Richard, which may explain why it didn't sell and was quickly withdrawn by Columbia. The other singles also are uncharacteristically raw and electric, more fascinating lyrically than musically.

Of the previously unissued live recordings, the best are "It's All Over Now, Baby Blue" and "Visions of Johanna," both stunning solo turns from Dylan's tumultuous tour of England in 1966; "I Don't Believe You," with the Hawks in 1966, just before they became the Band; and the swirling surreal/allegorical odyssey "Isis," from 1975's Rolling Thunder tour.

The other live cuts are "Romance in Durango" (a live version from Rolling Thunder) and "Heart of Mine" (1981), and they provide a fine confirmation of Dylan's suggestion that "the point is not understanding what I write but feeling it." Of course, when the layers of imagination and the internal rhymes and rhythms are as compelling as Dylan's, you can do both.

Of the alternate takes, the most moving are "You're a Big Girl Now," a melancholy ballad from "Blood on the Tracks," and a technically weak but emotionally powerful solo version of "Forever Young," done by Dylan in the office of his publisher so they could copyright the lyrics.

Other previously unreleased songs are "Baby I'm in the Mood for You" (a playful but slight outtake from the "Freewheelin' " sessions in 1962), "I Wanna Be Your Lover" (Bo Diddley meets the Beatles thanks to the Hawks in 1965) and "Abandoned Love" (a bitter ballad about marital breakup -- sometimes known as "St. John the Evangelist" -- that was left over from "Desire"). "Jet Pilot," a 30-second electric snippet from the "Highway 61" sessions, offers a sample of Dylan's humor.

There is surprisingly little carry-over from Dylan's two "best-of" collections: only 14 songs, nine of them from Volume 1. If nothing else, "Biograph" should send a whole new generation scurrying to investigate Dylan's 28-album catalogue, even as it sends his old fans back to their well-worn copies.

Columbia's isn't the only new Dylan box to hit the streets recently. There's also a 10-record bootleg called "Ten of Swords" by "Zimmerman," a collection of the most notorious bootlegs of material from 1961 to 1966. There are outtakes from the first four Columbia albums, three sides each of the Minnesota and Gaslight tapes, the Carnegie and Town Hall concerts and a side of sessions with the Hawks in 1965, just before the British tour; the set finishes with two sides of the electric set at the Albert Hall. It too features a booklet and pretty good pressings, and almost 25 minutes of music a side.

New and old fans will also be interested in "Lyrics 1962-1985" (Knopf, 524 pages, $21.95), an expanded edition of the 1975 collection supplemented by 122 new songs, liner notes and other writings. The sheer poetry is astounding, even more so because it is incomplete without the music, and especially without Dylan's heart and voice. Even if Dylan seems uncomfortable being held up as a mythic symbol of a generation and a culture, he should relish the power that his songs -- old and new -- can still generate.

In the end, maybe it all comes down to one Dylan song. A different Dylan song for everyone, of course.

"Biograph's" gem is "Up to Me," one of several brilliant leftovers from "Blood on the Tracks" (though Roger McGuinn recorded it on one of his solo albums). Like so many of Dylan's songs, it is a tale of separation and renewal, sung hauntingly with just guitar, bass and harmonica.

Two verses -- one early, the other at the end -- seem to sum up what it's all about, what it's always been about and what I hope it will always remain about for the man Crowe defines as "a lone figure with a guitar and a point of view."

If I'd thought about it I never would have done it, I guess I would've let it slide

If I'd lived my life by what others were thinkin', the heart inside me would've died

I was just too stubborn to ever be governed by enforced insanity

Someone had to reach for the risin' star, I guess it was up to me . . .

And if we never meet again, baby, remember me

How my lone guitar played sweet for you that old-time melody

And the harmonica round my neck, I blew it for you, free

No one else could play that tune

You know it was up to me.