The Bootleg Series has completely transformed the way that Bob Dylan's fans view the chameleonic artist’s staggering output. In the 20-odd years since the release of the first three volumes of the collection, Dylan has continued to put out paradigm-shifting outtakes and gorgeously restored live shows, primarily covering his iconic era from 1962 to 1975. From the 1966 Royal Albert Hall Concert (Vol. 4)—in which Dylan and his backing band shocked the world by going electric halfway through the set—to the recently released Basement Tapes Complete from Dylan’s legendary 1967 jam with The Band (Vol. 11), the Series has provided countless revelations about the artist’s songwriting development, recording process, and live idiosyncrasies.

Until now, the Bootleg Series has tragically offered only scattered visions of Dylan’s in-studio process during his pivotal move from folk to rock. This week, however, Dylan is releasing “every note recorded during the 1965-1966 studio sessions, every alternate take and alternate lyric.” NPR First Listen is presenting an 80-minute sliver of the result, a massive, 18-CD compendium of all the tape run in the creation of “Bringing it All Back Home,” “Highway 61 Revisited,” and “Blonde on Blonde.” While the sheer size of the release makes premature any survey statement on how the cuts will alter perspective on Dylan’s magical year—somehow already 50 years in the past—the first glimpses show just how engaged Dylan and his brilliant band were; every piano line, organ chord, and guttural yodel is remarkably ready for record. The collection, dubbed in full “The Bootleg Series Vol. 12: The Cutting Edge 1965-1966,” provides further proof of Dylan’s revolutionary zeal and genius assemblage of talent.

One of the most exhilarating elements of the Bootleg Series is its ability to communicate across volumes. “She’s Your Lover Now,” one of Dylan’s greatest songs, did not even officially see the light of day until it surfaced on Vol. 1-3 in 1991. The burst of up-tempo paranoia, in which Dylan seemingly confronts both an ex-lover and her new beau, is punctuated by pounding piano and surreal glimpses of drunken mistakes that grow in aggressiveness until they fade out mid-phrase. The track, which officially was initially slated for the seminal “Blonde on Blonde,” offers a uniquely baroque pop sensibility in conjunction with a much more acidic eventual album.

Vol. 12 offers several alternate versions of “She’s Your Lover Now.” The seeming best of the bunch augments the bare piano chords of the original with Al Kooper’s trademark organ, which sounds much like it does on the official cuts of “Like a Rolling Stone” and several tracks on “Blonde on Blonde.” Dylan, who is often unclear in his lyric about who, exactly, he is eviscerating in his tirade, changes the lyrical denouement of the song from “You better talk to her ’bout it / You’re her lover now” to “You better talk to her about it / She’s your lover now.” With this switch, the tangled web of the song’s perspective further complicates.

Hundreds of little instrumental and lyrical clues are included throughout the anthology. Here, the hard drive of the familiar “Absolutely Sweet Marie” is replaced with light arpeggio, suggesting a softer tone to the song’s confusing distinction between loving lyric and acerbic instrumentation. At the start of the take, producer Bob Johnston asks Dylan, “What’s the name of this, Bob?” to which the crooner responds, plaintively, “Where Are You Tonight, Sweet Marie?” Even the title is delightfully softer than that of the famed final product.

While “Vol. 12” can be endlessly parsed and explored from an almost historiographical perspective, it also contains some simply beautiful, vulnerable listens of Dylan without artifice. The artist’s vocal on Take 1 of “She Belongs to Me,” for example, almost sounds as if he is crying; his voice wavers and wanders around his ode to his lover artist who “don’t look back.” On record, “Visions of Johanna” is Dylan’s slow drawl about his frustrated acceptance of Louise, who is “all right” but “just near,” and his pining after his apparent real love, the elusive Johanna. On “Vol. 12,” however, one version showcases a sped-up, angrier track that feels more like a gorgeous tell-off than a sad ballad.

It is hard to criticize a work that provides such a window into one of the most important years in any artist’s musical trajectory. Even if the collection was badly produced and musically messy, it would still be a priceless cultural document. The gracefulness of so many of the songs, however, suggests that much of what Dylan produced during 1965-1966 had something fundamental to say about popular music. “Vol. 12,” at least at first glance, just might exceed any reasonable expectation for Dylan’s glorious throwaways.