In an age of pop culture anniversaries, this decade has been a forced march of celebrations marking 50 years of the vaunted accomplishments of baby boomers in the 1960s.

Tommy, however, is only 49. The Who's majestic rock opera about a deaf, dumb, and blind boy who becomes a pinball-playing cult figure that turned the British band into a global phenomenon came out in 1969.

But as far as Roger Daltrey is concerned, it's 50 already.

"In my mind, Tommy was born in '68," says the band's frontman, who will sing the 24-song opus penned by his bandmate Pete Townshend at the Mann Center for the Performing Arts on Tuesday, backed by the Chamber Orchestra of Philadelphia and members of The Who's touring band. "That's when the songs were written and we started recording it."

The legendary microphone-twirling Daltrey, who's 74, grew up in the rugged Acton district of London and was a sheet metal worker before joining Townshend, drummer Keith Moon, and bass player John Entwistle in a band that was called the Detours and High Numbers before settling on The Who.

Daltrey is known for his working-class ethos — as opposed to Townshend's art school proclivities. The always-threatening-to-quit Who — who scheduled their first farewell tour in 1982 — don't have any tour dates in 2018, so the singer is out working on his own.

"I was offered to do this tour on the arts circuit, and I found it very interesting," said Daltrey. He spoke on the phone from Washington, three shows into the tour. "And I have to keep singing," he adds. "At my age, if I stop singing for any length of time, my voice will go."

The cover of Roger Daltrey’s album “As Long As I Have You.”
The cover of Roger Daltrey’s album “As Long As I Have You.”

In addition, to the Tommy tour, Daltrey has just released As Long As I Have You, a solid collection of mostly older R&B covers that harken back to the repertoire of the early days of The Who. It's his first true solo album in 26 years.

For Daltrey, Tommy means reconnecting with the music that transformed the life of The Who. On Tommy's release day in May 1969, The Who were in Philadelphia, playing a weekend of shows at the original Electric Factory at 22nd and Arch.

"Things in our career really started to speed up from that day, really," he says. "I remember the Electric Factory, of course. We always had a great time in Philly, always great audiences, like any blue-collar place. Tommy was the key in the ignition, from then on the audiences grew steadily. It was shocking."

Another Philadelphia connection to that vintage Who era is heard on the Live at the Isle of Wight album recorded in 1970. Daltrey introduces a tune by saying, "This song is called 'Water.' In Philadelphia, they call it 'wooder.' "

He laughs at the memory, and recalls the communication problems the band faced while trying to break into America.

"I do remember the problems we used to have getting people to understand us. We were such green Cockneys. We hadn't developed the language skills to put ourselves across in America. They used to look at us like, 'Are you French?' "

In recent years, Daltrey has done charitable work with Children's Hospital of Philadelphia on behalf of Teen Cancer America, an extension of the Teen Cancer Trust, the UK organization he's also deeply involved with. In 2014, he did a benefit for CHOP with Joan Jett at the Kimmel Center.

The concept behind the cause that he founded with Townshend is that teenage cancer patients benefit from being treated together in their own hospital wards rather than mixed in with young children or the general population. Daltrey is extremely well versed on the subject.

"Adolescents are neither children nor fully formed adults," he says. "They get rare cancers, they often get late diagnoses. They have to deal with all kinds of things that are very, very different, and they were being situated in children's hospitals next to 2-year-olds and 5-year-olds."

Daltrey had a sister who died of cancer at 32, but he became heavily involved in the issue mostly because "it just makes sense to me. It's a way to improve patients' survival and welfare very cheaply." So far, Daltrey says, 11 children's hospitals in the U.S. have special teen wards, with seven more about to go on line. And for the sum of $100 million, which he calls "small change" in terms of medical fund-raising, "we could cover the whole of the U.S."

Daltrey's focus on the plight of teens is in keeping with The Who's roots as a band that emerged from the Mod movement in England back when Daltrey sang Townshend's lyric "Hope I die before I get old" in "My Generation." Sharp-dressed teen scenesters wore suits and ties, rode scooters, listened to American R&B, and decorated themselves with the Union Jack.

After Tommy lifted the band to a higher commercial plane, Townshend revisited the culture on Quadrophenia, the 1973 double album that's arguably the band's greatest achievement.

In that era, Daltrey and Townshend had a famously contentious relationship. In a 2014 interview in the Daily Mail, Daltrey recalled an incident in which Townshend came at him with a guitar "so I ducked the punch and hit him. It was a very clean uppercut. It knocked him spark out."

He says the tensions between him and Townshend, who plays guitar on As Long I Have You, have often been overblown. "What you have to realize is that a lot of interviews are done to give you guys a sound bite. It's rock wrestling. You say a lot of things to fire things up."

"I've always been pro band," he says. "I've always been a team player. I recognize how lucky we were to have found each other, and found the chemistry to become what we became as a band.

"The thing that's important about Pete and our relationship more than anything else is that we were always totally honest with each other. He would call me out and tell me like it was, and I would do the same for him. And with him it's so important because he could have died of sycophantitis through the '70s, '80s and early '90s. And that can kill an artist.  … If I didn't like it, I'd tell him. Maybe I was right, maybe I was wrong. But it would make him think."

The title track of As Long As I Have You is the Bob Elgin and Jerry Ragavoy tune that was a hit for Philadelphia soul man Garnet Mimms in 1964. Daltrey co-wrote two tracks: "Certified Rose" and the ballad "Always Headed Home." Otherwise, it's entirely covers sung in Daltrey's now heavier voice, which has thickened considerably over the years.

"This is the music that The Who were playing before Pete started writing songs," Daltrey says. "And that's why I wanted to do it. To sing those songs now. With the life experience I've had, they've got a very, very different thing going on. You can hear that direction in our first album, in the James Brown songs we were doing. I was singing all the notes then, but of course I hadn't had the life experience, so it was more like being a mimic than the real deal. Now it's for real."

Daltrey began work on the album in 2015, but he had to put it aside while battling a case of viral meningitis that he told Rolling Stone in 2016 was so intense that "if death would have come, I would have welcomed it."

"I'm OK now, but it was touch and go there for a while," he says, sounding unbothered. The illness didn't affect As Long As I Have You,  but it did alter his perspective.  "It made me realize how lucky I've been in my life. And what an amazing life it has been."