At the brilliant and accessible "Court and Spark," in 1974, fans wanted Joni Mitchell never to grow up. She was the illuminator of "sweetness in the dark," the trademark romantic boho whose lyrics were staples in post-adolescent journals. As she took flight from her raw, "Blue" emotionality and headed toward a more literary, less melodic style, her audience clung to her bygone image with the obstinacy with which they cling to their own youths.

On the phone from Los Angeles, her adopted hometown, Mitchell explains that when fans ask her, " 'When you gonna make another "Blue"?' or 'When you gonna make another "Court and Spark"?' " her answer is simple: "I'll never make another. Those are ingenue works about things I'm not concerned with now." Happily married to bassist-producer Larry Klein, Mitchell says that "so many people out there have broken hearts that they want me to bleed for them. They want to keep me single and bleeding forever."

And so, in the last 15 years, the Canadian-born Mitchell has become a pop pariah, rejected by an audience waiting for another "Help Me" or "Both Sides Now," which Judy Collins made into a Top 10 hit. They have been mystified by her pioneering explorations in jazz and Third World rhythms, now acceptable courtesy of Sting, Peter Gabriel and Paul Simon. Her politically confrontational lyrics, particularly on 1985's "Dog Eat Dog," were met with the sort of blunt hostility that greeted Dylan when he found God.

"I was not a protester in the '60s," Mitchell says in a Canadian accent still strong after 25 years in the States. "I was a protester in the '80s, when no one was protesting. I felt it was a nasty job, you're reviewed as negative, but somebody had to do it because everyone was in the midst of their shallow, money-grubbing rah-rah."

Now, in a surprising development, the tide has turned on Joni Mitchell once again. "Night Ride Home," her new album, has won a unanimously warm welcome from both critics and audiences (who made it No. 2 at both Boston's Tower Records and at all seven Newbury Comics, and No. 4 at the Strawberries chain during its first week of release). While not a carbon copy of her early '70s work, "Night Ride Home" is a listener-friendly work, favoring buoyant melodies and emotional frankness over gloom-and-doom social criticism.

Mitchell views the acceptance of "Night Ride Home" in terms of musical modality. "The album is mainly variations on the key of C, a lot of C major. People like major chords - major chords are happy, positive chords. It's a very sunny modality, this album, and friendly. It's not that it's a smile button in any way, because there are moments of minor, where it's tragic reevaluation and yadda-yadda."

She says she didn't try to concoct a crowd-pleaser - the "sunny modality" and nonconfrontational lyrics are simply a mirror of her own emotional state. After the "dissonance" and "heartlessness" of the '80s - not to mention some intense dental work - "only a positive sunny chord would do. I kind of stroked myself and wrote accordingly and found out other people needed the stroke of those warmer chords, too."

And indeed, Mitchell's temperament right now seems to match that of "Night Ride Home"; on the phone she is confident, accessible and warm. Calling herself "outspoken," she is willing to talk for more than two hours, elucidating her career and her songs with the sort of painstaking objectivity that has helped her to produce nearly all of her 16 albums singlehandedly. She laughingly says she places interviews "somewhere between 'Truth or Consequences' and a criminal deposition," but that "interviews for this record have been quite pleasant. Through the '80s, when it was find-the-underbelly-and-stick-it-to-'em kind of interviewing, it was pretty rough."

Aside from Mitchell's insistence on the C-major appeal of "Night Ride Home," the album also offers listeners an intimacy that has been missing from her recent albums. It is confessional, and not didactic, in style. Captured by the melancholy of growing older, the artist behind "Night Ride Home" is forgiving and compassionate, reminding herself as well as her listeners, "I am not some stone commission/ Like some statue in a park/ I am flesh and blood and vision/ I am howling in the dark." After a long season of discontent, she has "come in from the cold," as the title of her new single has it.

While she will wax eloquent about her many tuning selections, Mitchell resists a similarly probing personal interpretation of her lyrics. Over the years, she has suffered from a public eager to see her work strictly in terms of her own life. Surely it was Joni herself who "couldn't let go of LA, city of the fallen angels," as she sang on "Court and Spark." Surely it was Joni herself who wanted to "wreck my stockings in some jukebox dive," as she sang on "Blue."

On the contrary, she says, her songs - old and new - are a form of method acting. "It makes no difference if it's you or not. It's life. You can play any character with vitality. Whether you take your libretto from someone else's experience or from your own, you take it because you understand it. Because you 've been through it."

Linking the singer to the song betrays the song's "universality," she says. "When Nat King Cole used to sing, they didn't think, 'Oh, that's Nat singing about himself.' Something terrible has happened between the song and the audience since those days. Too much attention has been given to the artist, and not enough to the song."

Mitchell, of course, was notoriously victimized by the pop-cultural need to pry beyond the music into an artist's private life. With rumors of her love affairs common fare among rock fans in the early '70s, Rolling Stone magazine published a chart of her supposed romantic entanglements with other musicians such as Graham Nash and James Taylor. Mitchell, still miffed by the piece, calls it "unfair."

The new album may renew the guessing games, since the premise of a number of the songs is the mire of amour. "Two Grey Rooms," for instance, is about a woman 's lugubrious obsession with a lover of 30 years ago. Who is he? " 'Two Grey Rooms' is not autobiographical," Mitchell insists. "That's the point. You'd never know. I identify with the story. It's the strangest story of obsession I ever heard of - all romance has an element of obsession. I feel it as much as anything autobiographical."

Mitchell says that despite her stable marriage to Klein, who has worked with her on the last four albums, "I can still sing sad love songs. If they think, 'Well, she's not really sad, therefore it's bullshit,' then they got me in a Catch-22 that I can't get out of." What we do know about Joni Mitchell is that in the late '60s she "came to the city," New York, after studying art in Alberta and singing at folk clubs in Toronto. Her quick marriage to singer Chuck Mitchell over, she began to play the Greenwich Village circuit, connecting with the people who would take a important role in her career, including David Crosby and recording-industry honcho David Geffen.

Initially, she was best known as a disarmingly honest songwriter, responsible for Collins' "Both Sides Now" as well as a group of songs performed by Tom Rush. But by 1971 - the time of her third album, "Ladies of the Canyon," with the early environmental anthem "Big Yellow Taxi" - Mitchell's piercingly sweet voice became as valued as her lyrics.

As her important role in the shaping of female folk-rock conventions has come to light over the years, Mitchell has been placed at the root of a family tree that includes women as diverse as Suzanne Vega, Tracy Chapman, Shawn Colvin, Ferron and Rickie Lee Jones. To this day, young female singer-songwriters are compared to Joni Mitchell by reviewers simply because they are young female singer-songwriters.

"It's unfair to both of us," Mitchell says. "It robs her of her identity and shows how very little they know about the intricacy of my work. Initially, it's flattering, I suppose, because it tells her she is like something that she imagines has succeeded. But if it hangs over her too long, she's bound to get mad at them and me. And this has happened, and then they start attacking me. They go around through Europe or something like that going, 'chilly Mama.' ' Mitchell laughs heartily at this phrase.

Since her years as the textbook "Joni Mitchell," her singing voice has changed radically. No longer simply high and crystalline, it has grown into a less flexible but more nuanced instrument. This is not a problem for Mitchell, a heavy smoker: "There would be people who would lament if the vocal range shrunk. But you can still wield it. Sometimes voices with great range are almost too much - they dazzle. Voice to me is to communicate. Sometimes, by dazzling, it makes it standoffish.

"It was always too clean before. Songs like 'Cold Blue Steel and Sweet Fire,' for instance - it's nice, that clear-voice singing. But a voice with more life and crackle of experience - Dylan's voice always had that crackly quality - would bring out some of the theater that a clear soprano can't."

Thematically, "Night Ride Home" is a response to Mitchell's 1974 album, "Hejira," which was a bittersweet homage to the highway. With strikingly similar jackets, the albums also share "the same tuning except for one string," Mitchell says. Somehow it's fitting, then, that Mitchell has not toured in almost a decade, and probably won't take "Night Ride Home" on the road. She says she doesn't travel well, that her voice needs a rest, that her drummer is in Sting's band . . . but it's hard not to think that Joni Mitchell, a self-professed "night owl," would simply prefer to spend her nights riding toward, and not away from, home.