VANCOUVER.- Sarah McLachlan was just 30 hours from beginning her first full-band tour in a decade, and she could not sing.

She was in the final heave of preparation for eight weeks of shows stretching through late November that commemorate “Fumbling Towards Ecstasy,” the sophisticated 1993 album that turned her into an avatar for the sensitive, mysterious singer-songwriters of ’90s radio. But three days into a string of seven-hour rehearsals, her voice collapsed, the high notes so long her hallmark dissolving into a pitchy wheeze.

So onstage in a decommissioned Vancouver, British Columbia, hockey arena, a day before a sold-out benefit for her three nonprofit music schools, McLachlan only mouthed along to her songs, shaking her head but smiling whenever she reached for a note and missed.

“It only goes away when I project, push out,” she said backstage in a near-whisper following the first of the day’s mostly mute run-throughs. She slipped a badge that read “Vocal Rest” around her neck and winked. “Luckily, that’s only a third of what I do.”

For the last two decades, McLachlan, 56, has contentedly receded from the spotlight and the music industry she helped reimagine with the women-led festival Lilith Fair. Since 2008, she has been a single mother to India and Taja, two daughters from her former marriage. With rippling muscles that suggest a lean triathlete, she is now a devoted surfer, hiker and skier who talks about pushing her body until it breaks. Although she writes every morning, waking up with a double espresso at the piano in her home outside Vancouver, she has focused on motherhood and the Sarah McLachlan School of Music, offering free instruction to thousands of Canadian children since 2002.

A few years ago, she finished a set of songs about a pernicious breakup but reckoned the world didn’t need them; she hasn’t released an album of original material since 2014. “What do I want to talk about?” she said months earlier during a video interview from her home, swaying in a hammock chair. “I’m just another wealthy, middle-aged white woman.”

McLachlan, though, now may be on the verge of a renaissance. She is amassing a $20 million endowment for her schools, and exhaustive interviews for a Lilith Fair documentary just wrapped. In a year, her youngest, Taja, will head to college. For the second time, McLachlan’s life is opening toward music.

While revisiting her catalog to build this two-hour concert, which begins with a clutch of personal favorites before pivoting into a muscular interpretation of “Fumbling Towards Ecstasy,” she flew to Los Angeles for multiple sessions with producer Tony Berg, who has worked with Phoebe Bridgers and Aimee Mann. She has cut at least a dozen songs there, including a gently psychedelic cover of Judee Sill’s “The Kiss.” She has more to write. “I’m so energized by music, now that I’m living and breathing it every moment,” she said. “It’s a very different feeling.”

During the day’s second rehearsal, however, she tempered her enthusiasm with tacit worry about her voice. She told her tour manager that Taja would soon be backstage, probably with a prednisone prescription. “Mom, I’m already here,” the 16-year-old screamed, 20 rows back in an otherwise empty arena. “I have your medicine! Do you want it?”

McLachlan couldn’t hear her. She nodded to her band and started a song called “Fallen,” humming to herself.

DURING SUMMER BREAK between sixth and seventh grades, McLachlan’s friends in Nova Scotia labeled her a lesbian. She had indeed kissed another girl, practicing for a boy. She instantly became a pariah, a middle-class kid from a conservative family surrounded by wealthy bullies.

“I became poison. Then they started calling me ‘Medusa,’ because I had long, curly hair,” she said. “There was physical abuse, too. I thought, ‘I am on my own.’”

There was little quarter at home. McLachlan was the youngest of three adopted children that she said her father never wanted. Since he tormented her older brothers, her mother — unhappy with marriage, depressed by circumstance — responded to her daughter with equal disdain, ensuring everyone was miserable. “I didn’t have a relationship with my father, because my mother wouldn’t allow it. If I showed him any attention, she wouldn’t speak to me for a week,” McLachlan said, lips pursed.

Music, however, became her refuge. She graduated from ukulele at 4 to classical guitar at 7 after the family moved to the provincial capital. She struggled in school, skipping class to hide in the empty gymnasium and play piano there. Although she despised the hard stares and high expectations of recitals, she begged to join a band. Her parents relented to a few hours of Sunday practice. The group’s first show, for several hundred dancing kids in a student union, was transformational.

“I was being seen, and I was being accepted,” she said. “It was the first time I felt that way.”

That night’s headlining act included Mark Jowett, who was then running a small label, Nettwerk, in Vancouver. Stunned by McLachlan’s voice and verve, Jowett urged her to move west and start writing songs. Her parents insisted she finish high school and college. Soon after meeting the label’s co-founder Terry McBride, she defied them anyway. They barely spoke for two years. “She was green but really disarming,” said McBride, McLachlan’s manager until 2011, in an interview. “Her ambition was to get out.”

McLachlan soon cut a ponderous debut informed by the folk of her youth — Cat Stevens, Simon and Garfunkel, Joan Baez. Jowett and McBride wanted a producer to push her. When they asked Pierre Marchand, who had worked with the Canadian folk royalty of Kate and Anna McGarrigle, what he’d do with McLachlan’s music, he seemed flippant, saying he’d find out in the studio. “My manager was like, ‘I don’t like this guy.’ But I’m like, ‘I love this guy,’” she recalled. “It was all about exploration.”

The pair decamped to the New Orleans studio of iconoclastic producer Daniel Lanois, where their professional relationship turned physical. (“We wrote a lot of songs naked,” Marchand admitted, laughing.) That intimate bond proved critical when an ascot-sporting representative from McLachlan’s American label, Arista, stopped by to listen. When he didn’t hear a marketable single, they didn’t capitulate. They told him to leave.

“It was a defining moment for me in deciding how I wanted to control my future,” McLachlan said. “I thought, if this is what being famous and successful means, to compromise this thing that feels so important, I don’t want it.”

They gambled correctly. The success of “Solace,” McLachlan’s second album, drifted from Canada into the United States, where it was released in 1992, buying her and Marchand goodwill. They spent a year and a half in a studio in the Quebec countryside, McLachlan often walking home by moonlight while Marchand built late-night loops and atmospheres. The result, “Fumbling Towards Ecstasy,” remains an uncanny singer-songwriter record, her frank observations on betrayal, friendship and lust warped by his outré sensibilities. “I like it when it’s complex, when there’s not one feeling,” Marchand said. “It’s like a person.”

Marchand and McLachlan added the layered grandeur of U2 and the supple strength of Depeche Mode to these testimonials of yearning and loss. Critics lauded it as smart and sensual. Sales were stronger still: It went quintuple-platinum in Canada and sold more than 3 million copies stateside.

“I was in a punk band listening to a lot of hardcore — and, strangely, Sarah McLachlan,” said Leslie Feist, the Canadian songwriter who will open the U.S. leg of McLachlan’s tour. “I could hear her power, but it was being expressed more fluidly. It wasn’t about aggression. It was about conviction.”

As McLachlan’s profile grew, letters from stalkers mounted at Nettwerk’s offices, especially from an Ottawa, Ontario, programmer named Uwe Vandrei. They met once, and he slipped her a scarf. But after she read one of his pleas, she asked not to see more. Still, in the album’s opener, “Possession,” where bass pulses and guitars radiate above droning gothic organs, she worked to mirror his mind, to articulate his misplaced passions. When it became a hit, he sued, alleging McLachlan had lifted his words. Vandrei died before trial.

“I felt a strange sense of relief,” McLachlan said haltingly. “But then I thought, ‘Oh, my God, this is somebody’s son. Should I have tried to reach out? Tried to talk some sense into him?’”

The success of “Fumbling” — and the draining circus that followed, including conspiracy theories about label involvement in Vandrei’s death — helped spur McLachlan’s most historic defiance. She demanded to not headline every show, to be partnered with acts who could share celebrity’s weight. Promoters balked at the idea that women could carry such a docket, rankling McLachlan. She named a genre-jumping touring festival for Lilith, a woman repeatedly lambasted in sacred texts. Lilith Fair not only dominated the summer concert scene of the late ’90s but showed onlookers and executives that women were not music’s second-class citizens.

“I busked outside of Lilith and applied when I was 16,” said singer-songwriter Allison Russell, who made her onstage debut by performing McLachlan’s “Mary” alongside high school friends in Montreal. “She changed the landscape for women. She resisted what everyone told her she had to do.”

When McLachlan was the kid being bullied at school or alienated at home, music made her feel valuable. After her hit-laden 1997 album “Surfacing” (“Building a Mystery,” “Adia”) and Lilith Fair, it had also made her wealthy and famous, affording her a family and an activist legacy. She no longer needed the spotlight’s validation, getting it instead from her daughters and dogs, her music school and morning music practice. Her career steadily slowed, with more years passing between albums and her experimental ardor fading. She didn’t mind.

“I’m a middle-aged woman. You kind of became invisible,” she said, leaning in with a wide grin. She whispered, “And I really like that.”

THE ENCORE BREAK on McLachlan’s new tour is brief, maybe 40 seconds. At her benefit show in Vancouver, soon after the band faded from the title finale of “Fumbling,” McLachlan slipped through a black curtain and rushed to her polished Yamaha grand. She’s making a new record, she told the crowd, and she wanted to try a song alone: “Gravity,” her balletic ode to perseverance, to letting others lift you. If McLachlan discarded an album of breakup songs, this is a hymn for what comes after.

It is also a fitting prelude for “Angel,” the poignant 1997 ballad that became a maudlin punchline after scoring a commercial for the Society for the Prevention of Cruelty to Animals.

“I see it at the end of the day, and it’s like, ‘Hi, I’m Sarah McLachlan, and I’m about to ruin your day,’” she said of filming the commercial as a favor. “But that’s just not me.”

Before “Adia,” McLachlan told the audience she never explained that song, because it immortalized her taboo transgression: ruining a relationship by dating her best friend’s ex. “We needed to part ways for a while,” she said. “And I swear it was the hardest breakup I’ve ever been through.”

But they fixed the friendship, which has since endured divorces, children and new love. For years, that friend, Crystal Heald, urged McLachlan to take “Fumbling” on tour. “Thank goodness she forgave me,” McLachlan continued.

McLachlan is candid about her prospects. Relevance, she admitted, is a young person’s game that she has long resisted. She’ll be at least 57 by the time she releases new music, and she knows most people only like the old stuff. Still, when she told her forgiveness tale, the arena erupted with a wave of recognition for bygone mistakes and second chances, for comebacks. Her audience has aged with her; stepping back into the spotlight, she is ready to have that conversation.

“I didn’t talk for the first 10 years of my shows. When the music was happening, I knew what I was doing. Take the music and my voice, and I’m 12 again,” she said two months before stepping onstage. “But in the last 10 years, I say whatever comes to mind. I feel more freedom daily to be who I am.”

This article originally appeared in The New York Times.