Justin Timberlake's November Album To Feature Material From '20/20' Sessions

 Photo by Jeff Kravitz/FilmMagic

Justin Timberlake performs during his post GRAMMY party at Hollywood Palladium on February 10, 2013 in Hollywood, California.

"We're going to take some of the stuff that we've already done, and of course create more music," says producer Jerome "J-Roc" Harmon.

Justin Timberlake's "The 20/20 Experience" is already the best-selling album of 2013 so far -- its current sales sit at 1.52 million, according to Nielsen SoundScan -- and, as the pop singer shared last month, another full-length is on the way this November. Producer/songwriter Jerome "J-Roc" Harmon, a close collaborator with Timbaland who worked on the entirety of "The 20/20 Experience," tells Billboard that JT's next album will draw from his unused "20/20" material, as well as from upcoming studio sessions.

"Before we came to the 10 [songs on "The 20/20 Experience"] that he wanted and the two bonus tracks, we had over 30, 40 tracks," says Harmon. "So I think he's going to go in, and we're going to take some of the stuff that we've already done, and of course create more music at the same time."

Harmon began working with Timbaland on the producer's 2007 solo album "Shock Value," which featured the Timberlake collaborations "Give It To Me" and "Release," and then logged time on Chris Cornell's Timbaland-produced 2009 album "Scream." During the recording of Timbaland's 2009 LP "Shock Value II," J-Roc helped out on the Timberlake-assisted single "Carry Out," during which the pop superstar started tinkering with an idea that eventually became his "20/20 Experience" single "Mirrors."

"'Mirrors' was something we started working on in 2009, and he just shelved it," Harmon recalls. "He's like, 'I'm gonna save this one, and this is gonna go on my album.' We never knew when he was going to put it out -- we were like, 'Aw man, you're in movies now!' We could have waited another 10, 15 years. But then he surprised us last year and said he was ready, and he brought ['Mirrors'] over to the project as well."

Harmon makes it clear that the eight-minute "Mirrors" wasn't originally written with such an epic scope -- in fact, the second half of the song, which deflates the rock-inflected glow of the beginning into a puddle of warm R&B, was literally conceived years later, and independently of the original track. "We segued each piece to go into another song, so if you were to break it up, that second part of 'Mirrors' is like a song by itself," he says. "Once we got all the songs that [Timberlake] knew he wanted on this album, then that's when we began to tie everything together, and the second part just fell in order."

Justin Timberlake Hits No. 1 on Social 50 Chart

While Harmon won't reveal much else about his future work alongside the singer and producer -- he also notes that he and Timbaland have multiple other projects in the works, but won't reveal with whom -- the rising studio presence says that working next to a pair of formidable pop presences was never an intimidating process.

"These guys are really open-minded about their craft," says Harmon, "and what other people have to bring in order to augment that craft. So it's more of a challenge mentally to think outside of the box, to not generalize things, which is what most people tend to do -- they like to ride the waves instead of create a big tidal wave."