AIX-EN-PROVENCE.- “Un bel dì,” the title character’s great aria in “Madama Butterfly,” begins with the soprano singing a hovering G flat. Giacomo Puccini writes in the score that the note is to emerge not just pianissimo, or very soft, but also “come da lontano”: as if coming from far away.

The opera is about a young Japanese woman convinced that the American naval officer who abandoned her will return, and “Un bel dì” narrates her fantasy of seeing his ship sailing back into the harbor at Nagasaki.

At the Aix-en-Provence Festival in France, Ermonela Jaho condenses that desperate illusion into a haunting filament of tone. What’s more, she sings the note while lying on her back on the floor in this bracingly intimate new production of the beloved work.

“The attack on the G flat, it’s like hope is being suspended in midair, it’s a sound like the ship appearing on the horizon,” Daniele Rustioni, who conducts the Lyon Opera Orchestra in the production, said in an interview. “And Ermonela does it. You wait for that moment and she delivers.”

Jaho, who turns 50 on Thursday, delivers these time-stopping threads of sound again and again at moments like Butterfly’s ethereal entrance, marked even softer than pianissimo; during her love duet with Pinkerton, the callous American officer, when she says that the stars are like eyes, gazing at them; and later, when she insists that when Pinkerton returns, their son’s name will change from Sorrow to Joy.

Barely audible yet theater-filling, with both the gauziness of a watercolor and the precision of a pen drawing, these high, quiet passages are a Jaho specialty, capturing the essence of her fragile, suffering characters.

“The pianissimi, they’re not only pianissimi; it’s the sound of the soul,” she said in an interview at a cafe two days before opening night. “It can be more dramatic than screaming.”

Jaho’s voice, while not huge, is secure enough that those pianissimi register even in vast houses. The Théâtre de l’Archevêché in Aix, where “Butterfly” is playing, seats about 1,200. But even at the Metropolitan Opera in New York, with over three times that capacity, Jaho dares to murmur, making the audience’s ears come to her.

Her combination of consummate technique and utter commitment — the cathartic sense that she is truly living the stories of some of opera’s most heart-rending women — has earned her ovations, critical praise and the adoration of her colleagues.

“The courage she shows onstage to give you 150% of herself, and more, is really unique today,” said conductor Antonio Pappano, the just-departed music director of the Royal Opera in London.

Andrea Breth, her director in Aix, said, “I’ve never worked with such a beautiful artist.” Rustioni said he told the festival, “I’m not interested in doing another ‘Butterfly,’ but if you give me Ermonela ...”

Funnily enough, for an artist whose trademark is pianissimi, she grew up in a military family in Albania thinking that opera was only shouting. But when she was 14, she saw her first, “La Traviata,” in Tirana. Not only did she fall in love with the piece, but she also immediately thought that she could have done it more believably than the soprano onstage. Her future was sealed, and a few years later she moved to Italy to study voice.

“I was a shy child,” she said. “So it’s interesting, even though I was a little timid, that I chose singing, putting my face in front of everyone. But I always felt free when I was singing.”

Violetta in “Traviata” became a touchstone role, one she has sung several hundred times. But there is no feeling of routine in her performances of it: Last year, she brought unsettling shivers of reality even to the Met’s dull staging.

“Sempre libera,” the aria that brings down the curtain on Act I, was scarily defiant, almost a mad scene. “Dite alla giovine,” in which Violetta abandons her dreams of love, was classic Jaho, hushed and sensitive.

“Of course, in forte she gets to you, and she can sing in the biggest theaters,” Rustioni said. “But the quality of the pianos, the purity of the sound in long notes and, most important, the long phrases with no breaths, that’s the gold of her technique. The suspension without breath keeps you on your toes listening to her. I find her magnetic.”

The production in Aix keeps the focus squarely on her, imagining “Butterfly,” sometimes an ornate spectacle, as a spare, concentrated chamber drama, with the chorus always offstage. The playing space is compressed to a couple of painted screens and chairs in a small room, with a slow-moving conveyor belt around the perimeter, moving characters around like the hand of fate. A handful of Japanese dancers in Noh masks linger at the outskirts, ominous symbols of Butterfly’s ancestors.

For all Jaho’s old-fashioned, all-in quality, her performance is notably uncluttered and restrained. In the first act, when Butterfly is still just a girl, she had none of the coquettish vocal affectations and gestures some sopranos bring to the part.

Her voice is straightforward and unembarrassed describing her unsavory past as a geisha; as her trusted servant, Suzuki, undresses her for her wedding night, Jaho’s face silently registers pure satisfaction. After intermission, she seems somehow older: her voice a shade darker, her posture more stonily mature. But nothing feels like overkill, and even her stunning delicate passages are organic expressions of the musical line, rather than tacked-on, look-at-me effects.

“Sometimes,” Rustioni said, “there’s a sense that for Butterfly you need a more powerful voice. But you don’t need all this power to get to the audience.”

While she pushes herself to her limits onstage, Jaho has been careful in the roles she takes on. Her repertoire these days is centered on the doomed heroines of the Italian verismo school of the turn of the 20th century, a style Jaho inhabits with rare sincerity and clarity.

That includes lots of Puccini — Butterfly, Liù in “Turandot,” Magda in “La Rondine,” Suor Angelica in “Il Trittico” — as well as Umberto Giordano’s Fedora, Francesco Cilea’s Adriana Lecouvreur and the nameless protagonist of Francis Poulenc’s intense, one-woman “La Voix Humaine.” Jaho’s 2020 album “Anima Rara” mixed chestnuts with verismo curiosities from the likes of Pietro Mascagni’s “Lodoletta,” Jules Massenet’s “Sapho” and Ruggero Leoncavallo’s “La Bohème” (rather than Puccini’s).

But, she said, “I know my limits.” She thinks the protagonists of Puccini’s “Tosca” and “La Fanciulla del West,” for example, are too heavy for her, as is Salome, which she’s been asked to sing in the past.

“I don’t think she should be singing Tosca or Aida or things like this,” Pappano said. “She’s a classic lyric soprano, with all that implies about the heart and vulnerability and the ability to sing softly. And she should remain that. Singers don’t always have to be in transition. They can reap the benefits of being at the top of their game.”

Jaho’s performances culminate after the opera has ended. Some singers come out for their bows with smiles and waves, even after the most tragic pieces. But Jaho seems almost destroyed. At the opening night of “Madama Butterfly,” she practically stumbled across the stage, leaning on the set’s thin columns for support as the audience cheered. Surely this was an over-the-top act? But Jaho insists — and everyone who works with her agrees — that she is not putting it on for show.

“After a performance, I’m completely empty,” she said. “I gave everything. I don’t even want to come onstage for the applause; I want to leave. I’m shattered.”

Breth, her director, said: “In a way, I think she’s like a child. Very vulnerable, and you have to be really careful with her; you have to give her shelter and a lot of love. But I can’t think of another Butterfly than her.”

This article originally appeared in The New York Times.