Wiz Khalifa and Charlie Puth, 2015

Wiz Khalifa and Charlie Puth photographed at The Gansevoort Presidential Penthouse in New York on April 30, 2015.

Bjarne Jonasson

Wiz Khalifa's Furious 7 soundtrack smash "See You Again" has become an adult contemporary radio hit, bulleting for a second week at its No. 15 highpoint on Billboard's AC chart.

Um, small detail: The pop/rap hit has crossed over essentially without Wiz Khalifa, the song's lead artist.

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A version with only featured vocalist Charlie Puth's vocals, including new sung verses, is drawing significant airplay at the format after Puth, who co-wrote and co-produced "Again," recently released his solo, rap-free version on SoundCloud.

Roadrunner Promotions, which has worked the ubiquitous Atlantic Records single to radio, hasn't specifically promoted Puth's version to the conservative AC format, instead happily (and even bemusedly) accepting airplay of whatever version stations might want to play. "Again" topped the Billboard Hot 100 for 12 weeks, tying the record for most time spent at No. 1 on the chart for a rap hit, and crowned the Pop Songs, Rhythmic Songs and Rap Airplay radio-based genre charts. So spins at AC radio at this point are largely gravy after the song, which has sold 3.3 million downloads through the week ending July 16, according to Nielsen Music, has feasted on so many formats.

While Puth's SoundCloud version of "Again" served as the springboard to the song's AC crossover, one entrepreneurial programmer enhanced its airplay potential by bringing back enough of the original's familiarity, although still sans Khalifa.

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"When I first heard [the original], it was obviously a one-listen hit record. Then I thought, 'Wouldn't it be great if there were a mix for AC radio, with just Charlie?,'" recalls Tony Lorino, who was program director at the time of Adult Pop Songs chart reporter KZPT Kansas City. (He's since been promoted to PD at WSTR Atlanta. Keep reading and it'll become clear why.)

"By coincidence, I had just liked Charlie on Facebook," Lorino says. "Mark Zuckerberg and the Facebook gods must've heard my wish -- they know everything -- because Charlie then put his version on SoundCloud. It's just him on piano."

Lorino put that recording of "Again" on-air on KZPT. (Even many adult pop stations, in addition to ACs, shy away from rap, an extenuation of the formats' "no rap, no hard rock" roots. Roadrunner says that adult pop stations are playing a combination of the original and Puth-only versions of "Again," which rises to No. 2 on the Aug. 1-dated Adult Pop Songs chart.)

But, says Lorino, Puth's SoundCloud posting was "lacking a little … It was too acoustic."

That's where Lorino proved that some programmers in 2015 -- despite the position's segue, in many cases, to a less-hands-on "brand manager" role (that often includes vital oversight of digital platforms) -- aren't afraid to get their hands dirty in a production studio. (OK, in 2015, digital editing is less dirty than in the old-time days of cutting tape and facing the dangers of razor blade cuts, but still.)

Lorino, in tandem with KZPT morning show producer Brian Sieminski, decided to mix Puth's piano-based reworking of "Again" with rap-free elements of the original single. (Hear the result above.) "[KZPT] doesn't play rap, for the most part. We've found that if we have versions of songs without rap, they tend to do better for us. There's a method to our madness."

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As Lorino notes, AC edits removing rap from big hits are common. Many AC stations played, and continue to play, Katy Perry's "Dark Horse" without Juicy J's rap, just as they now play Taylor Swift's (potentially-Perry-related) "Bad Blood" without Kendrick Lamar. The difference is that it's easy for a label or station to snip out a featured rapper's verse, or simply play an album version that doesn't include a rapper, who's often added for a pop radio/retail single edit.

It takes much more ingenuity to reinvent a song by subtracting its lead act. One similar prior instance, although the artist and label saved radio the trouble of doing the work: After Jay Z and Alicia Keys topped the Hot 100 for five weeks in 2009 with "Empire State of Mind," Keys released the Big Apple anthem solo as "Empire State of Mind (Part II) Broken Down," likewise a piano ballad with new sung verses. Keys' take rose to No. 18 on AC.

(Rihanna also remade Eminem's seven-week 2010 Hot 100 No. 1 "Love the Way You Lie," on which she first guested, as a solo, stripped-down song, although it didn't chart on AC.)

Ultimately, Lorino's radio acumen has helped "Again" expand to a new audience (even if Khalifa might not necessarily reap extra benefits). Other AC stations heard about KZPT's mix, and the station has shared it. They've also similarly tweaked their own edits, according to Roadrunner. Says WKJY Nassau, N.Y., program director Jon Daniels, "To be able to be a part of a pop-culture phenomenon, a top-charting song from a blockbuster movie, in a way that fits sonically with our core sound, is a win for AC radio."

"[KZPT] gets a call or [social media] message a day saying, 'Where can I get it?,'" Lorino says of the altered "Again." (The station has played the song more than 800 times through July 21.) "If an artist puts something out on a site like SoundCloud, they're saying, 'enjoy my art.' If I'm a radio person, and it fits my station, why shouldn't I play it? I'm giving consumers what they want, in the office and around their families.

"It's a great song. And now, it's a great fit for more listeners."