Since the release of Kendrick Lamar's Damn, a lot of talk has focused on the album-closing track "Duckworth," which tells an eerie story about a long-ago run-in between TDE chief Anthony "Top Dawg" Tiffith and Lamar's father. But a good part of what makes the track so emotional is the music. We talked to the man behind the beat(s), 9th Wonder.

You recently posted on Instagram a 2010 tweet of Kendrick's where he asked to work with you. Did you see that at the time?
I didn't, as a matter of fact. I had just joined Twitter maybe a year before or something like that, so I wasn't used to always looking at my timeline. Now, all of us are fixated with our timeline. But before, I didn't know you've got to keep up with your timeline, man! So I didn't see it at all. As a matter of fact, the first time I actually saw that tweet was when DJ Booth did an article on the tweet, and I was like, "Wow, where'd you dig this up from?" They said, "Man, he tweeted you seven years ago." And when I went back and I traced it, I said, damn, that was the day before I actually met him, Schoolboy Q, Ab-Soul, and Jay Rock at Rock the Bells. It's nuts.

What happened was, the day he tweeted me is the day I arrived in L.A. for Rock the Bells 2010. So that was a Friday. But the next day, I met him and Ab and Schoolboy and Jay Rock all at Rock the Bells, and they were saying how much they were fans and they listened to me for years and everything. At the time I'm talking to him, I've heard about him because I knew about Overly Dedicated and a few other things. So I was like, what's going on. But he never mentioned the tweet to me—he wasn't like, "Yo, I tweeted you yesterday." He never said anything about it. So it got lost in time.

After [that meeting], I put him on a song with my group Actual Proof called "Super Genius." I put him on another song that was on The Wonder Years called "Enjoy," and that was with Warren G and Murs. Those are the two songs that I put him on. He sent his verses immediately. He did a joint with Rapsody on her mixtape For Everything called "Rock the Bells."

After that, we kept in close contact. With Kendrick, "close contact" means you talk to him for about three weeks straight, and you won't talk to him again for maybe nine months. This is how he operates. He turns himself off from the world, and I totally understand that, 100 percent.

So we kept in touch. Rapsody ended up on To Pimp a Butterfly because they've always been fans of each other. After that, he mentioned to me, "We gotta do something." I played him like 15 beats in the studio one night. Out of the blue last summer, he sent me a text of just a short video of him playing part of the song that you now hear as "Duckworth."

I knew the beat was mine. I heard the words, and I was like, "What's this?" He just put back, "LOL." To me, that keeps it fresh. I think being on the internet all the time, there's no new turn-ons, there's no freshness to anything. Kendrick keeps it fresh. 

Out of the blue last summer, he sent me a text of just a short video of him playing part of the song that you now hear as 'Duckworth.'

Had you already sold the beat to someone else by then?
No. The three beats that ended up being on "Duckworth," I had played for three different people

The three different people, they picked it, but they never used it at all. And these aren't three different everyday rappers. These are three different rappers rappers—rappers-everybody-knows rappers. But they never used the beats.

Of those three beats, I think the oldest beat on there would be the first one. They're in order of appearance. The first one is the oldest, the second one is the next-to-oldest, and then "Atari" by Hiatus Kaiyote would be the last one. So he took all those three. I've done three beats before with Murs on "Walk Like a Man." He took those three, and that's what you got.

What made you decide to use the Ted Taylor sample for the main section of the song?
People always ask me, why do I choose samples the way I choose samples? I don't usually choose samples with voices in them, because I care about what the soul singer is saying. It's more of the instruments behind it. I'm trying to capture the instruments behind what the sample is saying, instead of the Blueprint algorithm where the sample says something, and you have to rap around that. That was legendary in its own right, but I like the instruments behind the voices. It just felt good to me, man. 

Did you remember that Ludacris had used that as well?
Yeah. That's "Splash Waterfalls." The thing about it is, if you're going to use a sample somebody else used, you better flip the hell out of it, you know what I mean? It's a producer rule. This is hip-hop. The late Guru said it: "Rap is an art, you can't own no loops/It's how you hook it up and the rhyme style, troop." So that's what it is.

You're going to always run across the same records. We all buy the same records and mine the same records and find the best part of all these records. You're gonna find the same records. That's gonna happen. You may find something somebody else used, but you may hear it a different way. I think a perfect example of that is "Nautilus." 

"Nautilus" by Bob James has been used 50 million times. But 50 million ways. So that's what it is. I just heard [the song] and I said, nobody's ever done it this way. And I wanted to make it with a West Coast bounce to it. So that's why I chopped it up that way.

So you weren't with Kendrick when he did the vocals for it?
No. His process is a little bit different from everybody else's. However, after the song was done, I got to touch the session myself—do the drops I wanted to do. Big shouts to Khrysis, who is also in the Soul Council with me on our label Jamla, because we both mixed the record together. When we got to hear it in its entirety, I was like, "Wow." The first thing I asked [Kendrick] was, is this a true story? 

Can you tell us what his answer was?
He said yes, it's a true story. That's the thing that's been going around on the net. Top Dawg has confirmed that it's a true story. The beauty of that is, he chose to tell that story, and we're like four albums in. Usually, people will tell that story the first time.

Right! You've got something that good, you want to tell it first thing.
But he told it four albums in, at the end. It's like, "In summation of everything you've heard from me, now let me tell you how it all came about." And that's his genius when it comes to when he chooses to write about something, and how he chooses to write about it.

Can you tell me about the mass vocals at the beginning and end of the track? Was that something you had anything to do with?
The singing part when the track first comes on? Nah. Kendrick does great concept albums, so that's his way of tying albums together. The Kid Capri part I had no idea about [either]. That was incredibly dope. What I am responsible for are the three beats on that record and drops.

Was that your first Kid Capri drop in your career?
You know what? I think so. And I've met Kid Capri several times, talked to him several times. I think next time when I see him, our conversation's going to be a little different. [Laughs.] It's always good, but now I'm going to be like, "Yo." Because Kid Capri, to my generation of hip-hoppers, and hopefully to this one too, is legendary.

Finally, are there any more plans for collaborations with TDE that you can tell us about?
No, I cannot. [Laughs.] My label Jamla Records and Top Dawg Entertainment, we have a special bond and we both believe in uplifting the culture in any way we possibly can. They have the utmost respect for us; I've got the utmost respect for Kendrick, Top, Ab, Schoolboy, Isaiah Rashad, Sir, SZA, Lance Skiiiwalker, Hollywood Dave, retOne, everybody over there. They look at my camp the same way, and they treat us the same way. And I just really respect that a lot.