Over a soft piano riff wafts the unmistakable voice of Sade, singing a song to her son. The lyrics she wrote for the piece — her first new track in 14 years, titled “Young Lion” — are steeped in empathy and regret. “Young man, it’s been so heavy for you/ You must have felt so alone,” she sings. “I should have known.”

She’s addressing her real-life son, Izaak, whose identity as a transgender man escaped her perception for some time. “Shine like a sun,” she sings to him. “You have everything you need.”

Massima Bell, a musician, model and activist who is transgender, said she’d never heard a song like that before. “It’s amazing to hear a legendary musician like Sade sing about her heartfelt experience as the parent of a trans child,” she said in an interview. “It’s incredibly powerful.”

It’s also humanizing, nailing a key goal for the sprawling new musical project that contains it. Titled “Transa,” the album, which Bell worked on as a creative producer, is the latest venture from Red Hot, the organization co-founded 35 years ago by John Carlin at the peak of the AIDS epidemic. The organization started with a star-studded album titled “Red Hot + Blue,” designed to raise funds for the fight against the disease.

In the decades since, Red Hot has released more than two dozen sets, involving hundreds of top musicians, to benefit a wealth of related causes. (The organization said it has given away $15 million over its lifetime, primarily raised by record sales.) Still, it has been years since it has focused on an issue with the topicality of “Transa,” a project due Nov. 22, which was partly inspired by the death of the producer Sophie in 2021.

“Sophie was a boundary- pushing, generation- defining musician and one of the most important trans artists we’ve ever had,” said Dust Reid, of Red Hot, who is one of the album’s key architects.

Carlin said the new project represents a return to the organization’s activist roots. “We’re living in a time when trans people, the most marginalized and vulnerable people in our culture, are being attacked and stigmatized, much like people with AIDS were in the ’90,” he said. “We’re doing this to make sure the culture wars are being fought from both sides.”

On Red Hot’s side are more than 80 artists, including many transgender and nonbinary musicians, who created 46 tracks, yielding over 3 1/2 hours of music. Exclusive tracks come from big names including Sade, André 3000 and Sam Smith, as well as scores of lesser-known trans musicians such as Nina Keith, a composer from Philadelphia, and Clarity, a musician from Los Angeles. Showcasing the music of less exposed trans artists was a key goal for the organizers.

Toward that end, the artists were given a wide creative berth, as well as ample opportunity to collaborate with each other. In one track, experimental composer Claire Rousay worked with Wilco’s Jeff Tweedy on a piece set to the William Blake poem “How Sweet I Roam’d.” In another, Korean American singer-producer Yaeji injected an urgent spoken word section into an original song by songwriter- artist Teddy Geiger.

Roughly half the songs on the set are new. The rest are covers composed by artists with both cultish followings (Judee Sill’s “Down Where the Valleys Are Low”) and classic hits (Sylvester’s “Mighty Real,” graced by hallowed vocals from Smith and Moses Sumney). The first single is a cover of “I Would Die 4 U” by Lauren Auder and Prince’s longtime collaborators Wendy & Lisa (Melvoin and Coleman), who played on the original track. The melding of cisgender and trans performers was crucial to the organizers.

“We wanted everyone to see themselves in this project,” Reid said.

The sheer length of the project makes a statement. “We felt this needed to be bigger than just a polite compilation record for a cause,” Carlin said. “It needed to be epic.”

The album’s title comes from a 1972 LP by Brazilian artist Caetano Veloso, which he recorded when he was living in London during his country’s fascist years. “Because he wrote the album while in exile, it provides a good allegory for how trans people are finding new ways of living,” Reid said.

The project features Veloso’s song from that set, “You Don’t Know Me,” performed by a group of artists including Devendra Banhart and the recently “rediscovered” transgender songwriter Beverly Glenn- Copeland, who at 80 is one of the set’s oldest stars.

Another historic reference point comes from a cover of the song “Any Other Way,” which became an improbable Canadian hit in the ’60s for soul singer and early trans performer Jackie Shane. Americana singer-banjo player Allison Russell recorded Shane’s song for the project several months ago at Mexican Summer studios in the Brooklyn borough of New York City, in a stripped-down version, joined by harpist Ahya Simone. “Let’s make this as weird as possible,” Russell said to Simone playfully at the session. She responded by adding increasingly filigreed riffs to the core song.

Jayne County, the 77-year-old pioneer of queer punk, contributed wit and energy to the project, performing a new version of her 1974 piece “Surrender Your Gender” with Kathi Wilcox of Bikini Kill and Laura Jane Grace. “Like most of my work, the song is tongue in cheek,” County said in a phone interview. “It has a serious side but the humor is important because it brings people in who might have otherwise been afraid of a song that talks this way about gender. The humor also makes it easier for anyone who’s struggling to accept their gender.”

However far-ranging and innovative the music may be, Carlin remains keenly aware that physical album sales have dwindled in the age of streaming, and the organization now focuses more on raising awareness than money. (Its biggest early releases, including “Red Hot + Blue” and “No Alternative,” approached sales of 500,000; a recent tribute to Arthur Russell and “Red Hot + Free” topped 20 million streams.) On Oct. 28, the organization will issue an abridged, physical version of the set as a single LP, emphasizing the most famous participants.

“This is just a pebble in the pond,” Carlin said, “but we hope the ripples will be profound.”