RIO DE JANEIRO.- In 1955, Milton Nascimento was 13, learning to sing and, devastatingly to him, hitting puberty.

“When I began to see my voice deepening, I said, ‘I don’t want to sing anymore,’” Nascimento, one of Brazil’s most important musical figures, recalled last week in an interview. “Because men don’t have heart.”

He was crying, he said, when a smooth, soulful croon came from the radio. It was Ray Charles singing “Stella by Starlight.” “After I heard that, I said, ‘Now I can sing.’”

Over the next six decades blossomed one of music’s great voices, an ethereal force that spanned octaves with emotion and verve, gliding seamlessly between a velvety baritone and a celestial falsetto.

Nascimento’s singular sound and ascent to the highest notes helped influence a generation of artists. In an interview, Paul Simon called his voice “silky magic.” Philip Bailey, a singer in Earth, Wind & Fire, compared it to “a beautiful Brazilian beach.” Sting described it as “truth in beauty.”

In Brazil, where Nascimento’s voice led singalong anthems and emotional ballads, the nation settled upon an even grander metaphor: “the voice of God.”

Now that voice has changed once again. Next week, Nascimento will release what he says is likely his final album, “Milton + Esperanza,” a warm, almost dreamlike collaboration with the American jazz musician Esperanza Spalding after 15 years of friendship between the two. Spalding arranged and produced the album and plays bass throughout, and the pair sing together on nearly every track. That includes a wistful duet in Portuguese between Nascimento and Simon — the first song Nascimento has composed and released in years.

There is little surprise that, at 81, Nascimento’s voice is not what it once was. It is quieter, unsteadier and at times straining to reach notes it once soared past. Yet it retains an undeniable warmth. It is weathered, broken in. And it provides a comforting presence throughout the album, like a grandparent’s hand in yours.

“He has a special essence, and it comes out in the music,” said Spalding, 39, wrapped in a shawl at a bakery here on a windy Brazilian winter day. “But it’s the thing he radiates all the time. When he’s watching novellas, I’m like, ‘Oh yeah, you’re the one who wrote that song.’”

She added: “It’s a mystery, and it’s beautiful.”

She had a point. A few days later, Nascimento was giving off a gentle, unmistakable aura as he sat on his couch here, in a tracksuit and Crocs, in front of the television where he watches hours of Brazilian novellas, or soap operas, every day. He smiled softly, praised everyone he mentioned and, over two hours, drifted from story to story, with many non sequiturs.

He recounted collaborations with the jazz greats Wayne Shorter, Herbie Hancock and Pat Metheny; told of meeting Paul McCartney for the first time last year (a framed photo of the two hung beside him); put on a song he wrote about his mother (“she taught me what it is to love”); and described several potential extraterrestrial encounters (in one, he saw what he believes was a UFO entering a Rio tunnel).

The conversation followed his stream of consciousness. His voice was soft, his answers short, his memory frequently failing him. In front of him was a pill organizer; behind him, five Grammys. Outside, workers banged on a new patio. He and his son had just moved in. Nascimento no longer walks well, and his previous address had five sets of stairs.

“I look at images from before the pandemic and it feels like 20 years has passed,” said Nascimento’s adopted son, Augusto, 31, who manages his father’s affairs. “My agony is not seeing this as his final work, my agony is knowing that I don’t know how many more years I have left with him.”

His father, however, did not want to talk about aging. “I don’t think much about this,” he said, clamming up. “I don’t. Really.”

Nascimento once remarked that unless an artist can find an audience, “you can be the biggest genius on the planet, but you’re going to end up singing in the shower.” For decades, Nascimento found an adoring audience, but he admitted that, since the recording of this album, he has stopped singing, even in the shower.

‘A Grand Synthesis’

Born in Rio in 1942, Nascimento was orphaned at 2 years old when his mother, a maid, died of tuberculosis. The daughter of his mother’s employer adopted him and moved to the Brazilian state of Minas Gerais, known for its cheese and kindness.

Nascimento — who goes by “Bituca,” a childhood nickname that stems from his pouty face — was brought up in a house of music. His mother studied music and his father worked at a radio station. He quickly learned the harmonica, the accordion and the guitar.

By his 20s, he was earning a reputation in music circles, and when he played three original songs at a televised music competition in 1967, the crowd — and the other competitors — were left stunned.

“It was a spiritual thing,” said Brazilian guitarist Guinga, who also performed at the event. “I feel the same thing today, 57 years later. He became famous overnight.”

Nascimento quickly became one of Brazil’s biggest and most influential acts. He was prolific, releasing more than 50 albums, including “Clube da Esquina” (“The Street Corner Club”), an emotive 1972 record made with a group of musician friends that many critics consider a masterpiece.

His sound was distinct, mixing various Brazilian genres as well as jazz, classical, rock and folk, making music that can be at times both pleasing and haunting. “He is a grand synthesis of the best Brazilian music,” said Nelson Motta, a Brazilian music producer and author. “An idol of the most sophisticated, most ambitious musicians.”

Nascimento collaborated with Elis Regina, Antônio Carlos Jobim and Chico Buarque in Brazil and with James Taylor, Cat Stevens and Duran Duran abroad, among many others. Bailey said in an interview that he and Maurice White — Earth, Wind & Fire’s other lead singer — traveled to Brazil in the 1970s to study its music. White met with Nascimento, and “came back raving about the experience,” Bailey said. “The next record that we did, we were all over the Milton Nascimento experience.”

Spalding first heard Nascimento while a student at Berklee College of Music when a friend put on Wayne Shorter’s 1974 album “Native Dancer,” which opens with Nascimento’s falsetto. “How is this on Earth and I didn’t know?” she recalled thinking. Now she admits she is incredulous when other people haven’t heard of him. “It’s like, ‘Do you know Bach?’” she said.

Spalding, who has won five Grammys, called Nascimento one of her greatest references. “Even for the beautiful arcs and unexpected melodies that you can hear in samba and a lot of Brazilian music, his is different, and it’s been absorbed into people’s marrow in Brazil, and I’m sure affected their consciousness as a people,” she said. “And he’s just, you know, over there in his house, just chilling, watching novellas. He’s impactful, but he’s not trying to be.”

‘Just Like a Master Painter’

In 2022, Nascimento embarked on a farewell tour across the United States, Europe and Brazil, singing while seated, in a multicolored cloak, as the band played around him. Spalding joined him onstage in New York and Boston.

At dinner one night, Nascimento’s son made a spontaneous suggestion: Spalding and Nascimento should do an album together. But it would have to be fast, as Nascimento’s voice was in good shape from the tour.

Though overwhelmed with previous commitments, Spalding immediately said yes. “That’s what canceling is for,” she said. (She had recently collaborated on another hero’s project: Shorter’s opera “Iphigenia.”)

After preparing at home in Portland, Oregon, and on the road, she traveled to Rio six times last year to record. She realized quickly that it would not be a “studio” album. Nascimento was most comfortable at home, specifically in the room with his television, in between broadcasts of novellas. They leaned mattresses against the walls to improve the sound.

“He’d be watching novellas, and he just shifts his chair and starts recording,” she said.

That did not mean, however, that he was mailing it in.

“The sophisticated perceptivity that he has is so amazing,” Spalding said. She recalled playing the nine-minute composition by Shorter that closes the album and asking what Nascimento thought. “He’s like, ‘Yeah, play it from the beginning.’” Then he improvised vocals. “He heard the texture and the composition and knew just where to put his sound,” she said. “Just like a master painter.”

Spalding said that while Nascimento’s age had constrained his voice, it had also added something.

“Physically, elders’ bodies can’t do the same things they could do 30 or 40 years ago. But the music sense and the awareness of composition and structure and sound and timbre feels even more sophisticated and refined,” she said, “even if they’re not speaking as fast or not gesturing as fast as you’re used to.

“So that was also really encouraging to see. Like, oh my God, we can keep doing this through our 80s? Just keep distilling and cooking down what we know, what we hear?”

‘The Thinking Is Clearer’

Simon, who is a year older than Nascimento and still writing and recording, said that age had a greater effect on singing than on playing an instrument, but that “even Tony Bennett was coming up with something at close to 95.” The mental aspect is affected in a different way. “The thinking is clearer,” he said, “but it’s slower.” (Simon said he’s at work on a new project, too: “As long as that impulse is there, I follow it.”)

“Milton + Esperanza” reimagines original Nascimento tracks; covers songs by Shorter, the Beatles and Michael Jackson; and includes new songs that Spalding said she wrote while thinking of Nascimento. The album features Simon; Guinga; the jazz singer Dianne Reeves; the singer-songwriters Lianne La Havas, Maria Gadú and Tim Bernardes; and the jazz saxophonist turned flutist Shabaka Hutchings, among others.

The affection between Nascimento and Spalding is palpable on the album, as they talk and laugh in interludes. Her voice appears to take his by the hand at times, guiding him over melodies. The result is an album that feels like a tribute to the man who sings on every track.

Last month, Spalding was back in Rio at Nascimento’s home to perform some of the album for a coming edition of NPR’s Tiny Desk series. His living room was turned into a set, with flowers, patterned rugs and several gold and platinum albums on the walls. Spalding was perched above the rest of the musicians with her upright bass, with Nascimento across from her, dressed in a Kangol-style cap and sunglasses.

On the first track, “Outubro,” the verse builds into a crescendo as the pair sing in harmony, ascending gradually to higher notes. On the first take, as Spalding climbed higher, she waved her hand to Nascimento to come along. But he couldn’t. He threw up a hand in surrender.

She smiled warmly and nodded in understanding. The band started over.

A few minutes later, when the crescendo arrived again, their voices pushed through together and held the note. As the line ended and the instruments took over, Spalding looked Nascimento in the eyes and smiled proudly, as if to say: I knew you could do it.

This article originally appeared in The New York Times.