After a No. 1 Billboard 200 debut last month for their latest album Blurryface, the two members of Twenty One Pilots are feeling even more confident about their summer concert schedule, which includes festival appearances and shows in Australia, New Zealand and Japan before a North American tour of the biggest venues the duo has ever headlined.

"It's a funny thing," singer and multi-instrumentalist Tyler Joseph tells Billboard. "I'll be in my home town of Columbus (Ohio) at a restaurant or something, and the waiter maybe asks, 'What do you do?' and I say, 'Oh, I'm in a band...Twenty One Pilots,' and he'll say, 'Cool, I'll check it out. I never heard of them.' And then I say, 'In September we're playing the Schottenstein Center,' and it's like, 'What?!' 'Yeah, there'll be, like, 14,000 people there.

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"There's so many people who have never heard of us, but I think what we've learned is you can't underestimate the power of a core fan base and people who believe what you're doing. I think they're the ultimate marketers. They're the ones promoting us. It doesn't matter what we post about ourselves on social networks or how many times we play live TV, even. It's all about those people, those fans who are telling other people about us. I think that's what we're seeing more than anything."

And playing live is when they can really feel the impact their music has. "What we see are more and more people who are kind of physically resonating with the songs," drummer Josh Dun adds. "We missed that while we were off making the album, so we were really excited to start playing live again, and it's picking up where we left off with having a person come to a show and leave telling their brother or sisters about it and stuff like that. It's this organic way to share music."

Twenty One Pilots have spots on the Bunbury Music Festival in Cincinnati and the Bonnaroo Music & Arts Festival in Tennessee before heading Down Under on July 4. Fests in Japan, South Korea, Canada and Ireland are also on the bill before the amphitheater/arena trek kicks off Sept. 8 in Washington, D.C.

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Joseph says he and drummer Josh Dun have "never been more excited about playing new music than when we start playing some of these new songs," and with good reason. The duo began working on the material during the latter part of the touring cycle to promote 2013's Vessel, converting the back lounge of the tour bus into a studio. "We wrote this record almost completely on the road," Joseph says. "Every night we were able to start playing two different people -- that person who got up on stage every night and then that person who went back in that lounge and started writing songs. So we were able to ask ourselves every night, 'What do we wish our set had?' We look at songwriting very much through the filter of live music, so we wrote 1) whatever we love and 2) what we felt our live set needed. Looking back on this new record as a whole, you can tell we were really influenced in that way."

That said, Blurryface is unquestionably a studio album. After working with just one producer (Greg Wells) on "Vessel," Joseph and Dun went for a team approach on the new album, with collaborators such as Ricky "Wallpaper." Reed, Mike Elizondo, Mike Crossey and Tim Anderson helming different tracks.

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"The songs we wrote were so different from each other," Joseph says, "so Josh and I did our research on these producers and what their strengths are, what they bring to the table. And we even dated a few more. Once we had the list of songs we wanted on the record we could tell which songs would work best with which producer. All these guys added something to the record, and we were very intentional about what songs they were going to produce. It really kind of kept everyone on their toes, but it was a perfect marriage with all these guys, so I'm happy we went about it the way we did and we're really happy about how it turned out."