Megaproducer Dr. Dre (real name: Andre Young) and Interscope Geffen A&M chairman Jimmy Iovine have received the lion’s share of press attention around Apple’s acquisition of Beats Music and Beats Electronics, but many consumers are completely unaware that pop star Will.i.am (real name: Will Adams) was a co-founder of the venture and its third equity partner.

That means he, too, is poised to financially benefit from the deal. But a rich musician getting richer isn’t why consumers and the business community should care about Adams’s quiet involvement in Beats; they should care because, like him or hate him, Adams’ tireless promotion of Beats products helped push them to mass recognition.

Speaking to Fortune by phone from London immediately after the acquisition was officially announced, Adams discussed his role in Beats and his reaction to the sale. Apple buying Beats is another sign of mainstream pop music’s ability to dictate culture, Adams said, and by extension exercise influence in the board room.

Below, an edited transcript.

Fortune: So the sale is official. This is good news, right?

Adams: This is the craziest rollercoaster I’ve ever been on. The past two months.

Were you involved in the talks and negotiations with Apple?

No. That’s Jimmy [Iovine]. That’s the master.

But you were a cofounder of Beats, which a lot of people don’t seem to know.

In 2005, I came back from tour. This was right after we [the Black Eyed Peas] launched iTunes and iPod with an ad that used “Hey Mama.” So we came back from tour and my whole world changed. In 2003, we hadn’t really taken off, and then we did the Apple ad, and boom, it catapulted Black Eyed Peas to a totally different stratosphere. Then we go on tour, and we notice in Europe they had a camera on the phone. People in the audience are watching the show through their cameras now. So I come back home, and I tell Jimmy, “We need to make hardware. The world has changed. Hardware, hardware, hardware, hardware.” So a year later, he said, “What do you think about headphones with Dre? I was on the beach with him and we talked. We’re going to do headphones and speakers, do you want to be part of it?”

[Author’s note: Jimmy Iovine’s version confirms this basic story; in a 2011 video interview with author and marketer Steve Stoute, Iovine said, “I was with Will.i.am one day and he said, ‘You know, the record business is all screwed up, it’s losing money. Jimmy, hardware… About a year later, I was walking down the beach, and I ran into Dr. Dre. He said, ‘Jimmy, my lawyer wants me to sell sneakers.’ I said, ‘Dre, fuck sneakers. Let’s sell speakers… Beats by Dre, headphones and speakers.’ That was the beginning of Beats.”]

Did you make a conscious decision to take a backseat and not be a prominent face of Beats? It seems like that’s what happened.

Well, no, everyone was doing one. They had Diddy Beats, Gaga Beats, Bieber Beats. And I didn’t want that, I wanted to be effective for the entire Beats, not doing just one SKU. I invested in my own squad of 40 developers to bring to market hardware products. So I didn’t want Beats to get in the way of my core work. But I love this company. Beats is amazing. It’s the most inspirational thing I’ve been a part of and had a role in.

Did you foresee it selling to another, larger company from the beginning?

I wasn’t consulting and doing the stuff I was doing in order to sell it. I was consulting for translation and adoption. People, culture, and aspiration. People wanting to be a part of something that felt like a movement.

So, then, is selling to Apple good for the company?

Yes, in many ways. It’s not just good for the company, it’s good for the culture. You have to look at it like, How is it good for kids in inner cities first? How do kids in inner cities not only dream about being athletes and musicians, but now, entrepreneurs, and bringers of new, disruptive, cool, lifestyle products. A whole new spirit just popped from this one announcement. The game has been elevated. No longer will [young kids say], “Yo, I got 16 bars. Yo, I’m out here hustlin.” It’s, “Yo, I educated myself so that I too can bring a consumer product to market. I too have ideas about the digital world. I too can be in the conversation.” And because it’s Beats by Dre, it’s going to happen in corners of America that you never thought would be bringing stuff to market.

And with Dre being the face of all that, do you wish, in hindsight, you had taken more of a public role? Any regrets?

No! Not at all. It’s not about me. My involvement, as I had promised, was to play my part. Just like Jimmy played a part in the Black Eyed Peas’ success. As a friend and a father figure and a role model and a mentor to me, I gotta play my part the way he played a part in my life. So I’m happy for Dre, but I’m ecstatic for Jimmy. That guy is my hero. And that’s exactly what this is about. Yeah, Dre deserves this for everything that he’s accomplished in sound and music. Jimmy, that guy is a mastermind. If my little seed of an idea turned into this freakin’ oak tree, awesome. It was just a little seed. But Jimmy planted it, he watered it, and every once in a while I came through the soil to help. And it inspired me for what to do on the stuff that I’m doing.

Are you able to share what your ownership percentage is in the company?

That wouldn’t be appropriate. You’re going to find out eventually, and I don’t want it coming from me. But I’m happy! I’m freakin… [laughing] very happy. All I know is, two months ago, Jimmy said to me, “The first few weeks of May I need you to make yourself available.” I said, “I’m going to be traveling, I’m going to be busy with all sorts of things. You’ve gotta give me some hint.” He said, “Will, I can’t. I just want you to know your life will change, in a major way, come the middle of May.” So, I made myself available, I stayed in L.A., I went to Marc Benioff’s commencement speech and hung out with my friend Marc. Now I’m in London, but it’s a great day.

What did Iovine want you available for? The meetings with Apple?

No. I still don’t know, to this day. But I’m overwhelmed. And hats off to Jimmy for keeping it under wraps. For like three or four weeks he was so distant. He couldn’t really talk on the phone. It must have eaten him up. Now everything makes sense. How hard must it have been to keep the excitement and the wonderful news to himself. But Beats… we are the best company on the planet. The timing of it all seems a bit surreal. The conversation I just had two hours ago with one of my partners [on a different venture], and now the announcement of this, it just seems like there’s a shift, and the new seed that’s about to blossom is really big.

What’s really so big about this acquisition? Why should people outside the business world care?

Apple and Beats, in a nutshell, is culture. It’s like, if there was a tagline, it’s “culture club.” Tech without culture is just tech, and it sits on a shelf, and six months later it gets replaced and it gets put in some warehouse or landfill because nobody bought it because there was no culture involved. So culture and tech is a powerful, powerful, powerful combination.

And what is the culture of Beats?

It’s lifestyle, it’s street, but sophisticated street. It’s athletics. It’s music and club and youth. It’s cool. It makes no sense. You cannot logically explain big headphones on your head, other than it’s just what you want to wear. You can’t explain baggy pants—even though it’s not comfortable, that’s how you want to wear them. It’s a culture thing. Look at what Angela Ahrendts did with Burberry. She made it the number one luxury product sold in China — a British brand. And now Apple has Angela Ahrendts: culture play. Jimmy and Beats: culture play. This is culture. They are forming a culture club. Because the only place to go right now is not how fast the chip is, because everybody’s going to have that ability, anyone can do that. The point is that the dominant power play at this point in time is culture, and the marriage of culture and tech. He or she who gets it right is king or queen. For a while.

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