When Linda Ronstadt's record label put out her fourth "hits" retrospective last month, she reacted as she always does: by doing nothing.

She didn't advise. She didn't pick the songs. She didn't lend an ear. "I never listen to stuff I'm finished with," she says. "I don't want to hear what I was struggling with back when. That's like staring at yourself in a mirror.

"You know what? If I were forced to sing [the 1974 rock hit] 'You're No Good' today, I think I'd bolt for the exits. Sure, it was good material for that time. But I like to move forward. I like to dream today."

Ronstadt, the seven-time Grammy Award winner, takes the stage with the Baltimore Symphony Orchestra for three Big Band shows this weekend. She has come to be called "first lady of rock" (courtesy of Rolling Stone) less by seeing her career as a succession of albums or eras than by feeling it through as a work-in-progress. Only passion for the present moment could have propelled an artist like Ronstadt through folk, rock, Cajun, bluegrass, sacred, mariachi, Broadway and swing music with nary a wayward step.

"Art is a way of processing emotions," she says. "There's always something current you're feeling, something new, a different story to tell." For 35 years she has shared hers, one passage at a time, mapping out a vista so sweeping it has taken on, in the end, the look of American music itself.

It started in Arizona half a century ago, where Linda, a sensitive child in a musical household, soaked up the joyful Latin folk her father sang and the Big Band standards, Hank Williams tunes and classical and opera epics the family enjoyed on the radio. It might surprise the millions of fans she made in her early hit-making years, but Ronstadt, born in 1946, never heard rock till she was 10. "When I left for California at 17," she said, "I wanted to play traditional music."

Moving on

She set her sights on the Ash Grove, the already legendary folk oasis in West Los Angeles where Doc Watson and Lightning Hopkins had taught, where bluesmen Sonny Terry and Brownie McGhee honed their chops, and where Canned Heat and the Byrds came into being. When Linda got there, she met finger-picker Taj Mahal and string wizard Ry Cooder, then in a band called the Rising Sons, who played dueling guitars each night, swapping leads on "Roll Out the Barrel." She ran into Kenny Edwards, the guitarist with whom she'd form the Stone Poneys, her first band, in 1965. She sang at jams that gave birth to the folk-rock form.

Even then, though, the brown-eyed girl with the platinum pipes felt some of the tensions that would drive her later career. She stunned young peers like Neil Young and Jackson Browne, but she found that rock-style numbers fared better in L.A. clubs than the down-home bluegrass and ballads she wanted to mine. The Ash Grove faltered; the Troubadour and the Whisky a Go-Go, which booked rock-based acts, prospered. "The pressure was so on to amplify, to do electric folk," she says. She still thinks of her pal Chris Hillman as a bluegrass mandolin picker, not a founding Byrd.

Ronstadt loved young writers like Warren Zevon ("Poor Poor Pitiful Me"), Karla Bonoff ("Lose Again") and Young ("Love is a Rose"), and already knew their work "embraced many genres," but in clubs, she had to work up rousers to cap her act. "You're No Good" and Buddy Holly's "That'll Be The Day" were "fun to do at the time, but weren't quite what I was after." They became her megahits.

When country rock - driven by Ronstadt and unknowns like the Eagles, Browne and Lowell George of Little Feat - took off in the early '70s, she found herself playing huge coliseums, which lent themselves to far broader sounds than she enjoyed making. She loved celebrity and gaining a huge audience, but the lifestyle drained her. "I hated those big arenas," she says. "I have common sense and a firm grasp of the obvious, and those are not appropriate places for music. Your music doesn't grow in them. The shows were more like cultural events, like studies in anthropology. It was one big animal act."

Her career became a treadmill. She sang constantly - in the shower, doing the dishes, on her way to restaurants - and loved rehearsing with her band and jamming in hotel rooms. She thrived on private music - like the kind she found when her tours would stop in Washington and she could sing with close friends like Emmylou Harris, Ricky Skaggs and John Starling of the Seldom Scene. At their feet she learned, through endless repetition, the vocal "barbs, arrows and curlicues" that give bluegrass its haunting tones. "It's a rigorous art form," she says, "as exacting as Indian music."

But away from Washington, the grind was too much, the canvas too large. "Make an album; do a tour. Make an album; do a tour," she says. "I wanted to be in a theater, where people were focused. I didn't want to be screaming over an amplifier. I wanted a more musical experience." The solution was simple: Gain access to the right venues.

She laughs when remembering how she pulled it off. Through a friend, she met famed Broadway producer Joseph Papp and "graciously told him what I was interested in - doing theater. I was, shall we say, blissfully unaware of the particulars of the art form. I didn't realize it was even more intricate than learning bluegrass." Papp knew Ronstadt had a nearly operatic singing range and auditioned her for Pirates of Penzance; she won a lead role. "I didn't have the technique for that kind of singing," she says with a laugh. "I sang real high, like a boy soprano. I kind of faked it. But there I was, singing onstage, in a real theater where I wanted to be. And people kept showing up, with money!"

Seeking richer sounds

Ronstadt felt it would take a lifetime to master show-tune techniques, and that she'd have to train out her own style to do so. But exposure to more layered music whetted her appetite for richer stuff. She listened more closely to two old family favorites, Sinatra and Ella Fitzgerald. With a push from her boyfriend, a Sarah Vaughan fanatic, she wound up crooning swing standards for a New York record exec. She cut a record with a hot jazz ensemble. "I was in way over my head," she says. "It was awful, unreleasable."

Her manager and record label opposed the new style, she says, and "they were right! It was crazy. But I couldn't shake it. I told them I had to do this material." She brought in Nelson Riddle, the arranger who had worked with Sinatra and other pop greats, and felt more comfortable with an orchestra. Her three albums with Riddle - What's New (1983), Lush Life (1984), and For Sentimental Reasons (1986) - went platinum and established Ronstadt as an "enticingly languorous" reader of Gershwin, Ellington and Hoagy Carmichael, in the words of Rolling Stone's Christopher Connelly. "There's so much for a singer to find in 'Skylark' and 'Guess I'll Hang My Tears Out To Dry,' she says. "I'll never get tired of them."

During the mid-'80s, the Mexican tunes Ronstadt grew up with came back to her. "I'd never learned Mexican music at any professional level," says the ever-meticulous Ronstadt, "just singing in the living room with my dad." She took on the rich, refined falsetto style it called for and worked with the Mariachi Vargas, "the best Mexican band in the world." The result: two award-winning Spanish-language albums.

Another influence grabbed Ronstadt when she heard the siren song of family and adopted two children, a boy and a girl. She recently moved to Tucson with the pair to tackle parenthood head-on. The gig has been the happiest - and hardest - of her life. "It's wonderful, but it's also exhausting!" she says. "I knew it would be the biggest job I ever undertook. And when it happened, it wasn't twice as much as I expected; it was 50 times as much! By 5, I'm looking for bed. I'm sound asleep by 8:30 or 9. I wake up about 45 minutes before dawn and wring my hands about smallpox and stuff like that. Somebody has to be awake to worry about these things."

Motherhood has turned the torch siren, now 56, into a guardian of taste. She approves, more or less, of family favorites Pink and Destiny's Child, but, "I can't stand to listen to the radio anymore," she says. She liked a Tucson hip-hop station for a while - it's in Spanish and English - but "it's so mean-spirited now, so much about cashing people out for being losers. The lyrics are so graphically about somebody's recent or anticipated sexual experience. I just think, 'Well, I hope you enjoyed yourself, but, yuck! - I don't have to know all the things you did. And shut up!"

Ronstadt recently bought her daughter an Eminem CD but couldn't let her keep it. "I'm sorry his mother wasn't nice to him," she says, "and I'm sorry he felt like he had to beat the [heck] out of his wife. But I can't have my daughter hearing that!" She listens avidly to NPR. The kids, now 11 and 8, know little of Mom's legacy. They're used to drifting off to the strains of her lullaby CD and thinking of her as a Spanish-language singer. Last month her boy asked why she never sang rock. "They had no idea," she says. "They think, 'Hey, let's shock Mom and play her some rock and roll!' To them, I'm just this incredible fossil."

If so, she's a fossil who thinks. "The great thing that's happened to me is that I'm not limited to doing the hits I did in the '70s," she says. "I really didn't want to get stuck with that, and cleverly arranged it so I didn't have to be." She has toured for years with the five-piece band she brings to the BSO, a unit that can blend with any symphony. "It's great," she says. "There are always new things to explore in the songs, and I can pretty much play when I feel like getting out and playing."

'One of the best'

Why Charm City? "The Baltimore Symphony is one of the best," she says. "There aren't many as good. A girl's got to go where she can get a good orchestra." The BSO is glad to have her. "No artist has more multigenerational appeal than [Ronstadt]," says Dori Armor, the symphony's community planning director. "And the musicians are thrilled to play with her, which you can't always say for the SuperPops shows."

Before parenthood, Ronstadt could focus her whole being on music - and did. "You're always thinking songs, singing on your way somewhere, solving some little phrasing problem in your mind," she says. But her 12-hour work days are behind her. She must make a conscious effort to sing nowadays and only performs when friends or management wrench her, on occasion, from her ordinary single-mom life. The BSO shows are her only symphony gigs this year.

But Ronstadt, as ever, looks forward. There will be shows with her Mexican band - "those guys are such great players and fabulous singers; I'm not even close to tired of them" - and possible summer dates with bluegrass mandolin king Sam Bush this year. Even as she ignores The Very Best of Linda Ronstadt - now available online and in stores - she'll be adding to her legacy.

And as ever, she'll stay connected to the moment. "There's always something current," she says. "You know, 'I went to Walgreens, and they were out of dental floss.' Stuff like that; whatever it is. The song is just a medium. There's always a new story."

Concert

What: Linda Ronstadt with the Baltimore Symphony Orchestra

When: 8 p.m. tomorrow and Saturday; 3 p.m. Sunday

Where: Meyerhoff Symphony Hall 1212 Cathedral St.

Tickets: $35-$84

Call: 410-783-8000 or visit www.baltimoresymphony.com