Pianist Christopher O’Riley has been sneaking Radiohead into the classical music world for years. As host of NPR’s child-musician showcase From the Top, he gets to pick the music that gets played during station breaks. Rather than Chopin preludes, O’Riley would draw up piano transcriptions of pop songs, which he’d then play without preannouncing. It’s not the boldest selection, but for an audience that may never listen to anything written since 1900, it’s enough to mess with their heads. “When we’d say ‘That was ‘Karma Police’ by Radiohead,’” recalls O’Riley, “we’d get these emails saying ‘Who is this Mr. Head and where can I find more of his beautiful music?’”

O’Riley knows a good routine when he sees one. He’s since released two albums of his Radiohead transcriptions, another of Elliott Smith, another of Nick Drake, and a compilation of various other bands including Nirvana, Pink Floyd, Tori Amos, and REM. His latest release is his biggest and broadest yet: Shuffle.Play.Listen, a double album for which he teamed up with cellist Matt Haimovitz. The pair take on modern classical on the first disc (Stravinsky, Piazzolla, Janacek), and then modern pop on the second (Arcade Fire, Blonde Redhead, Cocteau Twins, and of course, Radiohead). O’Riley and Haimovitz will perform both sets of duets Saturday at George Mason University’s Center for the Arts. After that, Haimovitz heads to Cincinnati, having just been tapped to perform the debut of Philip Glass’s “Piano Concerto No. 2” with the Cincinnati Symphony. O’Riley and Haimovitz spoke with Arts Desk by phone.

What makes you choose the pop songs that you end up playing?

O’Riley: I’ll pick any music of any genre that I enjoy playing. I look for a confluence of voices and music, each of which contributes to a musical texture. And harmony. I react to a nice set of chord changes. It goes both ways. Radiohead, for example, have been influenced by classical composers, [Olivier] Messiaen in particular. With Elliott Smith, he’s fully in the tradition of Cole Porter, Gershwin, and of course the Beatles.

For this album, Matt was interested in having on Arcade Fire, being from Montreal as he is. The choices had to do with pieces that were particularly suited by a more vocal impetus. For example Radiohead’s “Pyramid Song,” which has a quintessential piano-vocal sound. The whole idea was you need a sustained instrument to take on the vocal parts, and the cello is the most vocal instrument.

Haimovitz: I came much later into an interest in indie rock and jazz. Chris played in a rock band at one point. By the time I was 18 years old, I didn’t know there were genres outside of classical. Now I’m a big Jimi Hendrix, Led Zeppelin fan. I’ve done an arrangement of “Machine Gun” by Hendrix for eight cellos, and his “Star Spangled Banner” for four. And I did one for the heaviest Beatles song I could find, “Helter Skelter.”

Chris gave me a listening list, and I narrowed it down to what I wanted to emulate, and Chris narrowed it down further harmonically and texturally. John McLaughlin was a shared passion between us. I was really into that guitar solo on “Dance of the Maya.” It worked out nicely: me using the piano score and the two of us taking it apart and figuring out what my cello part would be like.

Some of your transcriptions are pretty straightforward, but others depart quite a bit from the source. Your “Misery Is a Butterfly,” for example, doesn’t really sound like Blonde Redhead’s “Misery Is a Butterfly.”

Haimovitz: That happens to be my favorite arrangement. It’s interesting that you feel like that. When you lose the words, you lose the rhythm section, and some elements take on a life of their own. We find our own trajectory within the piece. I feel like we were trying to get to the spirit or the heart of what they did. With Cocteau Twins, that’s the same feeling. We have to find some variety.

O’Riley: For “Misery,” I tried to come up with a piano part that would incorporate elements of the drum part. That entailed breaking it out and letting Matt be both solo vocalist and accompaniment. This created a set of choices not reflected in the original.

What kind of audience do you attract? Do you find you’re warming up classical audiences to rock more or rock audiences to classical?

O’Riley: It’s hard to say. Anecdotally, I have kids on my own website say “I love your Radiohead stuff, now I’m also going to check out Mozart.” Young people can be as entrenched and calcified in their musical tastes as old people.  The heartening thing is we’ve done some shows for really traditional audiences, like a mostly subscription audience in North Carolina. These were not people who knew who Radiohead was, but they were appreciative of the differentiation between genres. And because they heard there was some Stravinsky on the program, they were willing to give this other stuff a chance.

Haimovitz: It depends. At Notre Dame, there was an older chamber music audience but quite a few college kids. When we played Radiohead, people would howl and whistle. At Cerritos Center in LA, it was more of a classical crowd. At Yoshi’s in San Francisco, it was more diverse, being a jazz club.

Your duets have an intimate feel to them, and you, Matt Haimovitz, have made it a point to perform in smaller and nontraditional settings, like IOTA in Arlington. Will you lose any of that intimacy playing at a large concert hall like GMU’s Center for the Arts?

Haimovitz: I think you create your own feeling of intimacy. We incorporate some amplification. If it’s a great hall, we’ll do the classical acoustic, but when we play Arcade Fire, we’ll amplify. It’s kind of nice to let loose, and for Chris not to worry about balance.

O’Riley: I’ve had critics say they would never see any show that’s amplified. If you make that a proviso, you’re cutting yourself off from Tanglewood, the Hollywood Bowl, or any outdoors festival. You’re either open to new experiences or not. But I’ve never seen a mass exodus at intermission.

What are you hoping to get across to NPR listeners with From the Top?

O’Riley: We tend to lavish a fair amount of attention on young athletes, but there’s no less ambition and devotion to music with these kids. We’re dealing with a fair amount of musical backsliding in schools, regardless of the musical conscience of kids, and kids are the best emissaries for musical education because their personalities are on display as well as the music. The NPR audience is an older crowd, and they don’t need to be preached to about this. But at least they can be reassured that the next generation isn’t going to hell in a handbasket.

What’s it like to be the person who’s going to debut Glass’ new cello concerto? Being that it’s billed as the third part of a trilogy that begins with one of his most famous works, Koyaanisqatsi, followed by Powaqqatsi, is it at all intimidating?

Haimovitz: It was intimidating, but not for that reason. It was because I hadn’t played anything of his before this, or any minimalist composers. So stylistically, it was an entirely new direction for me. What I was afraid of was if things did repeat, Philip would want me to play them the same way, and I couldn’t do that. I need that sense of variety to form an emotional arc to the piece. But Philip wants that, and loves it. Once he trusts you, he expects the performer to make it his own piece. He lets go at a certain point. It’s a stunningly beautiful, romantic piece. Things repeat, but it’s harmonically very moving. The three songs in the trilogy are pretty spread apart. This one is definitely less minimalist, in fact, I wouldn’t even call it minimalist at all.

Christopher O’Riley and Matt Haimovitz perform at George Mason University’s Center for the Arts at Braddock Road and Route 123 in Fairfax on Saturday, March 24 at 8 p.m. $21-$42. Photo by Sarah Scott