When Kendrick Lamar released his sophomore LP To Pimp A Butterfly Sunday night a week before its scheduled March 23 release date, the hip-hop world collectively lost its mind sifting through the LP to attempt to uncover its secrets. With a sound so rooted in jazz and funk, the musicians behind the LP's 16 tracks came under the microscope. But a core group of names were familiar to K.Dot fans who saw the MC's performance on the final episode of The Colbert Report, with Anna Wise, Thundercat, Terrace Martin and Philly soul singer Bilal forming a core backing group for the album.

Bilal has a long history of hip-hop collaborations dating back to his work with Talib Kweli and particularly Common in the early 2000s. But the crooner's list of credits over the past 15 years is extensive and eclectic, with Jay Z, Scarface, Clipse, The Game, Diddy, Lupe Fiasco and The Roots among the names who have tapped into Bilal's skills over the years. Now Kendrick, whose new funk and jazz-soaked album is right in Bilal's lane, called on the Philly rhymer to add depth and soul to six tracks off his album. Of the six, Bilal has two feature credits—for the back-to-back "Institutionalized" with Wise and Snoop Dogg and "These Walls" with Wise and Thundercat—and four additional vocal credits, for "u," "For Sale (Interlude)," "Momma" and "Hood Politics." No matter how you look at it, his influence on the album is extensive.

This summer, Bilal is plotting the release of his fourth official album produced entirely by Adrian Younge. With To Pimp A Butterfly still less than two days old, XXL hopped on the phone with Bilal to talk about his involvement with the album, working with Kendrick and how K.Dot compares to some of the greats. —Dan Rys

XXL: How did you get involved with the album?
Bilal: I got a call from Kendrick and we just busted up from there, started talking about it. We had been talking about working together for a minute so everything just lined up perfectly.

When did you get the first call to work on it?
Few months ago. I went out to L.A. and we did some stuff and then I did some stuff out in New York with him. He's very hands-on with the music so he was there the whole time.

What was the vibe of those sessions?
It was a real creative vibe in the room. You know, a lot of the people who worked on the album are good friends of mine, you know—Thundercat, Terrace Martin, Anna Wise—so I kinda knew all of them from just hanging in the scene. So it was a real creative environment, you know. I respect all of those artists a lot, so it was a real creative vibe. Kendrick works crazy hours.

You're featured on two tracks but have credits on four more. It seems almost like you, Thundercat and Anna Wise were a core component of the album. Is that how it came together?
I think so. I did a ton of stuff; I didn't really know where it was gonna go, I was just doing stuff in the lab, you know. [Laughs] I like to work and go for it. So when I spoke to him he was like, "Man, I want y'all to be on the whole album." I thought he was just... I didn't know if that actually wanna gonna happen because a lot of people say stuff like that. You know, usually when you do a song you fall in love with every song you do after you finish it. [Laughs]

Have you heard the full album?
Yeah, pretty much. I didn't even realize that it came out last night but I heard the full thing [beforehand].

With "Institutionalized" and "These Walls," what did you think about those tracks?
Great, great. I haven't heard the final copy yet and I didn't even know it was out but Kendrick had played me the stuff a while back when we were mixing. So I haven't heard the final final copy, but I love it. I love that whole crew and the whole sound, you know. It's dope.

How is working with Kendrick similar or different to working with, for instance, Common or The Roots who you've worked with in the past?
What's similar about all of them is that there's always an organic connection; they're truly involved in every aspect of their music and it's the same way when I was working with all of those people that you mentioned. I was in the studio working with them and from the beginning to the end they were very involved. There's a certain passion that you can feel with a person who is willing to stay in the studio all day long until the song is done, you know? There's a certain focus that you can feel. And all of these cats have that.

Now, the thing that makes Kendrick different is his style and his approach. His approach is different... I think all good stuff comes from the same source and we're all kinda trying to draw from that same source in the universe so he's a good antenna right now. He's got his antennas up and you can feel that when you're in the studio with him.

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