Dave Mason can’t believe how long he’s been on the phone. Half a century into the kind of stardom that affords someone the spotlight, the 2004 Rock & Roll Hall of Fame inductee marvels at how much there still is to talk about.

“In the great FM [radio] days, music was culture,” he says. “Those deejays were turning you on. Whether you liked it or not, it was often something you hadn’t thought of. You got caught up in it either way. There was always things the music brought out.”

Founding and intermittent member of Traffic, Mason was a close friend to Jimi Hendrix. He was there when the fiery guitarist heard a pre-release of Bob Dylan’s John Wesley Harding and decided to record All Along The Watch Tower, enlisting Mason to play 12-string on Hendrix’s iconic rendition.

Playing on the Rolling Stones’ Street Fighting Man and George Harrison’s All Things Must Pass, Mason’s fingerprints are all over today’s album-oriented rock radio without even invoking his name. And on Sunday, August 18, he plays the Performing Arts Center as part of the Martha’s Vineyard Concert Series.

For those who prefer their rock a little softer, Mason’s work defined late ‘70s Adult Contemporary with songs like Let It Go, Let It Flow, We Just Disagree, Only You Know & I Know and So High (Rock Me Baby, Roll Me Away). Those songs felt for more ubiquitous than where they landed on the Top 20 charts. Part of it was the sense of melody which swept listeners up, taking them places that felt good. And when one really listened the songs were always more complicated than they seemed on the surface.

“There are 12 notes of music, 26 letters,” Mason offers. “A lot of combinations came out of those very few numbers. I always tried to write timeless things. . . So many points of human interaction are always emotions: love, hate, the things between the boys and the girls never change.”

He chuckles a little as he says this. Now in his 70s, he’s witnessed enough life and music to know. Citing his own catalogue, the man who toured with Delaney & Bonnie and Friends, alongside George Harrison and Eric Clapton, he marvels at Joe Cocker’s ability to redefine Feeling Alright.

“I wrote that 50 years ago, and it’s one of the top 500 covered songs of all time,” he says. “The song isn’t about feeling alright. It’s about not feeling so good, and asking myself ‘how am I doing?’ Then Joe got ahold of it and good-bye question mark.”

It was a delivery the affable Brit didn’t see coming. As he recalls, “Denny Cordell [the founder of Shelter Records] played it for me, and I thought, ‘Damn! Why didn’t I play it that way?’ I’m not so clinging to the song, I’d never be, ‘They screwed up my piece of work.’ But Joe’s version? That’s the beauty of music, it’s open to interpretation – and everyone gets their own interpretation out of it. What do you feel?”

Mason, who often feels stifled by the state of radio and appalled by the lack of royalties from streaming sites and other internet outlets, laughs a bit about where modern music is. For a kid raised in Worcester, England, who’s “not really trained to do anything else,” he finds his thrill onstage.

“It’s sad, really. The music we made was interesting, and you got caught up in it. The world was more open. Now people love to put things in categories, to label things. Where are the days of Bill Graham, where you’d have Miles Davis and a rock band playing together? I have somewhat of a pop sensibility, but I like all kinds of music — and it used to come together.

“Now I’m left with what I started out with at 16: standing onstage and playing. I feel a bit like the Fuller Brushman: ‘Hi! It’s Dave! I’ve got some music at the merch table. . .’”

Another warm laugh rolls down the line. Never one to play dour, Mason is making a point. But he’s also enjoying being out on the road with his mates. Occasionally sharing stages with fellow guitarist Jorma Kaukonen’s Hot Tuna, he’s teamed with Journey and the Doobie Brothers, done shows with Jim Messina and Richie Furay. He’s especially stoked about the R&B Review he had with Steve Cropper for a tour.

“I grew up on his music, because he played on so many hit records, it’s unbelievable to sing Midnight Hour with the guy who recorded it! Such great fun. And if it’s not fun, there’s no point in doing it. That’s the one thing that translates between age groups. That and authenticity. Because no matter the age, people know the difference.

“That’s why I love the live performance moments. Especially when you’re in that place where you’re not thinking about it, you’re just doing it. And I like being able to do it. I have no big message, you know. I’m not going to use my platform for any big political speech. People get enough of that crap everywhere.

“I want to take people out of the day-to-day. You can’t see music or touch it. But physically, mentally, emotionally, it can transport you. It conjures up places and times. It’s there. And then it’s gone. But that immediate mental and emotional impact? There’s nothing like it.”

Mason understands the power of what he does, the time-stamping of the songs and the transcendence of what happens when a band hits their peak. Having spent four months off the road, he is ready to get back at it.

“After 9/11, I was on the road, and ended up spending a few days on the Vineyard with friends. I had a couple days, but it was so many miles ago,” he marvels. “When I play this first show, I know I’ll be thinking. . . and the next night is Chicago, and everything will be kicking on, then the Vineyard is the third night and we will be there.”

Literally, metaphorically and no doubt, musically. For Mason, it’s all about letting go and letting the music take them.

Dave Mason performs at the Performing Arts Center at the regional high school on Sunday, August 18, beginning at 5 p.m. Visit mvconcertseries.com.