The volumes of Joni Mitchell’s glorious vault-clearing series of “Archives” boxed sets are organized by musical eras, and the first three were relatively tidy: the folkie ‘60s, the “Ladies of the Canyon” era, and her commercial peak, the sleek jazz-pop of the “Court and Spark” years and its era-soundtracking singles “Free Man in Paris” and “Help Me.”

“Archives Vol. 4: 1976-1980” is something different: the period when Mitchell pushed farther and farther away from her audience’s expectations. There she is on the cover in her ubiquitous beret, scarf and sweater, the epitome of mid-‘70s cool, taking one last look at something she was already leaving behind.

The music of this era sprawls across “Hejira,” with its shimmering electric guitars and stately songs of travel and fast flings; the headlong move into jazz with the sprawling “Don Juan’s Reckless Daughter” (which is unfortunately better known for her appearance in blackface on the original cover); the daunting “Mingus,” co-written with the titular jazz great; and finally the mighty “Shadows and Light” live album. It’s a challenging run that almost dared fans to keep up.

What we have here is a six-CD deep dive of the ephemera around those albums — and what a fascinating collection of ephemera it is: demos and early versions that show how far some of these songs traveled before their album versions, and live material that reinvents classics as well as her newer songs. Her fellow travelers include jazz greats Charles Mingus (as a songwriter), Jaco Pastorius, Pat Metheny, Herbie Hancock, Gerry Mulligan, John McLaughlin and Tony Williams, and a spot appearance from Graham Nash and Jackson Browne.

Ironically, it begins in a folkie setting: on Bob Dylan’s all-star, cocaine-fueled “Rolling Thunder Review” tour — which she tells an audience here was like “running away to join the circus.” But as usual Mitchell did not conform and, like she did at the Band’s “Last Waltz” concert, used the shows to try out new material. We hear her dropping songs from her days-old “Hissing of Summer Lawns” album and even “Jericho” (which wouldn’t see vinyl for two years) to enthusiastic but slightly nonplussed audiences. The recordings are sometimes rough, but the historical value is priceless: One track captures her at fellow Canadian national treasure Gordon Lightfoot’s house, talking to him about her dulcimer before she plays a gorgeous version of “A Case of You.”

The set remains in 1976 for three full discs, alternating between Rolling Thunder tracks, 20-odd songs from her own tours (including peppy versions of “Free Man in Paris,” “Big Yellow Taxi” and even “The Jungle Line”) and finally a beautiful batch of “Hejira” demos.

In the second half, she starts venturing further out. There’s an early version of the 15-minute piano-driven opus “Paprika Plains” and a lovely take of “Otis and Marlena” with a wildly tuned chiming guitar and gorgeous multitracked vocals. Next up are a brace of alternative versions from “Mingus,” including dramatically different takes of “Sweet Sucker Dance” (a “Drums and Vocals” reading with multiple overdubbed ghostly, jazzy vocals) and a take on “Chair in the Sky” that’s practically a torch song. More fascinating on paper but less in practice are five “early alternate versions” of songs from the album featuring Mulligan, Williams, McLaughlin as well as Jan Hammer and Stanley Clarke, among others.

The set’s final stretch is a truckload of live material from 1979. After a version of “Big Yellow Taxi” from an anti-nuclear rally in Washington DC (featuring Graham Nash and Jackson Browne on backing vocals, a long way from the canyon they and the song made famous), we get almost 25 songs from the “Shadows and Light” tour, which saw her accompanied by top-flight young jazz musicians of the era: bassist Jaco Pastorius, guitarist Pat Metheny, keyboardist Lyle Mays, saxist Michael Brecker and drummer Don Alias. It’s an unusually well-matched band, respectful of Mitchell and the material, and all manage to shine while staying in their lanes.

They roll through presumably every song played on the tour — which is a lot — across three different nights. It’s an impressively diverse set, bounding from “Big Yellow Taxi” to “Free Man in Paris,” from a playful “God Must Be a Boogie Man” to the free-jazz of “Goodbye Porkpie Hat,” solo renditions of “The Last Time I Saw Richard” and “Woodstock” so transformed from the originals they’re practically different songs, and a pair of polar-opposite tracks with the doo-wop quintet the Persuasions: her own majestic “Shadows and Light” and the Frankie Lymon classic “Why Do Fools Fall in Love.” The final song is a bebop-inflected take on “A Chair in the Sky” with her accompanied only by Hancock on electric piano. Her masterful performances throughout show, as much as anything, the full range of her catalog, influences and talent, and not least her gifts as a singer, which were arguably at their peak on this tour.

It’s also the end of something. Mitchell’s adventurousness had boxed her into a corner commercially, and by the time she returned in 1982, she was back with David Geffen, on his then-new eponymous label, with “Wild Things Run Fast,” a deliberately commercial album that featured a cover of Elvis Presley’s “Baby I Don’t Care.” After an awkward ’80 phase characteristic of her cohort, she returned to herself late in the decade and continued to release albums, some of them great, with decreasing frequency for the next 20 years before effectively closing the book on her recording career with 2007’s “Shine.” (Of course, she’s made several high-profile performances over the past couple of years, including the two-night “Joni Jam” at the Hollywood Bowl this weekend, but those are largely well-deserved victory laps.) But this is the last chapter of her struck-by-lightning phase, the kind of astonishing creative streak that Stevie Wonder, David Bowie and Neil Young also produced in a very different way during this decade.

Joni Mitchell has never been one to wait for people to catch up with her. On the basis of this era, a lot of them still haven’t.

from https://variety.com