When Howard Stern jumped from terrestrial to satellite radio, Sirius had half a million subscribers. Today it has 25.6 million. As he turns 60, Stern looks back at his career and sees radio on the verge of the next step in its evolution.

It doesn't take long to figure out how Howard Stern has risen to his unprecedented level of success.

Having arrived for the day's photo shoot and interview ("It's Howard Stern!" a man says, elbowing his friend as the 6-foot-5-inch radio icon walks past them toward the elevator, a scene similar to random fans praising him in an airport in his 1997 box office No. 1 hit "Private Parts"), Stern's curiosity is instantly noticeable.

Stern, who counts photography among his hobbies, inundates lensman Andrew Eccles with questions about angles, backlighting and poses. Also evident: Stern's humility. "Pretty good . . . for me," he says as he scans some of the just-shot images on the studio's laptop. "He makes me look like Brad Pitt." He pauses, then adds, "Those are some pretty good lights."

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Stern's thirst for knowledge and a penchant for not taking himself too seriously have fueled a career unparalleled in radio, or elsewhere for that matter. Considered in his early days as a PD's nightmare known for risqué bits and less than full adherence to the rules, his overwhelming ratings success proved his model valid. The eventual syndication of "The Howard Stern Show" brought him national acclaim and prominence, aided a pair of million-selling books, his box-office blockbuster and multiple network TV versions of his radio broadcast.

This month, the host of "The Howard Stern Show" will celebrate his 60th birthday with a star-studded birthday bash set to air live on SiriusXM on Jan. 31 (19 days after his actual birthday). The party is a gift to his loyalists—open only to active SiriusXM subscribers lucky enough to win their way in for a night of music, comedy and Stern interviewing special guests—with the festivities to be hosted by ABC late-night host and friend Jimmy Kimmel.

Ahead of the bash, Stern sat down with Billboard to discuss not only his first eight years at the satellite broadcaster but also all the media over which he's reigned in a career that led to his induction into the National Radio Hall of Fame in 2012.

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Billboard: You've had two great years at "America's Got Talent," SiriusXM is throwing you a big birthday special, you have a happy marriage, your staff is stable, and your co-host Robin Quivers is healthy after battling cancer. Is it safe to say that this is the most content you've been, personally and professionally?

Stern: That's absolutely fair to say. And thank God for that, because it's all been such an emotional roller coaster my entire career. Also, we're big on meetings and collaboration. I never say that I'm the show by myself.

The relationship with SiriusXM is great. [Editor's note: In 2011, Stern and his agent, Don Buchwald, filed a lawsuit against SiriusXM for allegedly failing to pay promised stock bonuses for helping the company exceed targeted audience growth. The suit was dismissed in 2012.] I keep a journal. About a year before I was going to Sirius [which would later merge with rival XM], I had just signed, and I said, "Sirius is at 400,000 subscribers," and I wrote down, "I can envision a day where there'll be 30 million subscribers." I told my crew and they said I was crazy. Now it's happening. We're up to 25 million paid subscribers.

A lot of my fellow broadcasters were so angry with me when I left terrestrial radio. They were like, "Don't talk about him." But I said, "Guys, there are more jobs for us. If satellite takes off, the Internet takes off, we're in the driver's seat—content is king!" I knew if satellite could be developed, it would be a great tool for all broadcasters.

At this point in my career, I feel more like a mentor than anything. The first day I got to Sirius, they brought me in and they stood up and applauded. They were applauding because they knew that I represented a future for the company. It was really debatable, but I said I will work to make this thing work because I believe in it.

This is my dream, and I feel like we've created a new home for broadcasters. I'm doing radio the way I wanted to as a little kid. Language isn't an issue. I don't have the government up my ass. It's fantastic. It's a great place to broadcast.

You seem appreciative that not only did your audience follow you to a subscription model, but that it's a template that can work for other broadcasters.

I'll give you an analogy. When I was in high school I was a really shitty student. But my father said, "If you go to college, I'll pay for it." I graduated [from Boston University] magna cum laude, and you know why? Because someone was paying for school. How dare I be that arrogant? The idea that the audience pays to hear it, I feel more of an obligation to deliver a great show and to evolve, to make my show new every day, and to find new talent and create new channels.

Let's get more specific: How do you see broadcasting evolving?

In my mind, I've got it all figured out, and I've got smart people who talk to me about it. I didn't come up with it on my own, but I really do see where broadcasters will be king. In 10 years, it will be so different. Every broadcaster who has real drawing power will control his own destiny, will be the actual medium.

We have a lot of ways we can go, and I don't know what the best way is, so I'm seeking the advice of experts. We're in a very aggressive discussion. People with real jaws are going to have an app, an environment. They're not going to need anything. Your fans are going to be able to talk to each other. You're going to have your own universe. We're so close.

Your contract with SiriusXM runs out at the end of 2015. Where do you see yourself in two years?

I don't know. There's no reason to leave. It's pretty fucking great. They're adapting. They understood from the beginning that content was the thing that was going to drive this model.

It's not enough to be a music service. The guy who I had my first meeting with about Sirius was Leon Black. Leon's a real bright guy, and not a radio guy. I was attracted to that immediately. Radio guys have a very limited range and view. We're saying, "Come to the party, we'll give you football, music, and more. Could you, after having Sirius XM, go back to listening to terrestrial radio? Could you ever go back to listening to all of the commercials?

I knew I could do a lot of business with satellite and that we could really change things. I got extra bold and said, "I think we'll take XM. We'll gobble their ass up, too." When I met with XM, I said, "I think whichever one of you hires me will end up winning." Sirius believed me, and I don't think XM did.

How much satisfaction do you get not only with XM, but also with the wake you left on the terrestrial side, going back to WNBC New York disappearing after you left, and later heritage stations WXRK New York and WBCN Boston?

Who could've imagined? I swear to God on a stack of bibles, when I first got into radio, I was this guy just trying to make a living for $250 a week. That was my goal. I never thought I'd ever have any money. I just wanted to do a really wild show.

It was such a slow process, and I'm a big believer in a slow process. If I had an intern who wanted to be on-air, I'd tell them to not work for me anymore, stop, go out, find a small market, and do that, none of this big-market thing. It's getting harder and harder to do that in terrestrial radio, but if you're able to go out and get an audience . . . see the ratings come back, see where you fucked up and see where you did it right. All of that is the testing ground for what you're going to be doing.

I feel so completely gratified that when I've left radio stations, they've crumbled. I don't care what anyone says; when you leave, you hope they don't do well. The idea that all of the Viacom stations melted down in the morning—and they tried everything—I love it.

I've always managed to make a lot of money for my employers. I've always worked with the sales department. Those people put in so many hours. Any broadcaster who doesn't have respect for their sales department is a fool, and you will not succeed. You have to work in tandem with the sales department. And, from getting to be friendly with sales departments, they are some of the funniest people. I'm convinced radio has it backwards. I'd fire all the DJs and make them be sales people, and let the sales people on the air. That's where radio is going: real conversation, real people, it's completely morphed.

Well, you're the one who started the notion of "real" people on the air. You're a trailblazer in terms of revolutionizing the talk radio format.

That all came out of listening to a lot of radio as a kid. When I'd hear a noise in the back of the room—probably a cart falling or somebody coming into the room—I was like, "Why don't they tell us what's happening? I want to know!" It killed me that they didn't bring it in.

Why were you the one to bring that in?

Again, I think a lot of people don't think outside the box. "We have to sound professional!" God forbid we hear something human going on. The best moments on the radio are when we're human: arguments, laughter. When I'd hear a broadcaster laugh because they couldn't control it, that was just great.

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