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The Making of ShrapKnel as Told by Curly Castro & PremRock

“I’m gonna put that battery in your back.”

Many moons ago, I penned a piece on the importance of rap duos. The writing was uneven and needed work, but my sentiment was strong. Rap duos are more than precious; they are essential to the fabric of hip-hop, how steel sharpens steel, and dope bars elicit even more dope bars between contemporaries. Pressing play on the self-titled, full-length album by ShrapKnel, composed of Philly’s Curly Castro, 43, and New York’s PremRock, 34, I found myself returning to my three-year-old piece and nodding along silently as Castro and Prem demolished production from the venerable ELUCID across 13 haunting tracks.

“My girlfriend and I have this very old-school New York apartment that’s really a gem,” Prem explains over the phone as sirens whir past. “It’s a basement apartment that opens out to a backyard. It’s this interesting apartment with all these knick-knacks in the back. And there was a desk, pulled apart in two parts, and I put it together. In the backyard, the sun is only out there from 10 a.m. to 1 p.m., so when I found [the desk], it was becoming spring, and I put it in the [sunny] area. If I wake up at 10 and work on everything I wanted to get done without a phone and computer, that was my goal. I started having good ideas at this desk, and that’s when the ShrapKnel idea actually came. That was probably three years ago.”

Shrapknel by ShrapKnel is “a series of thoughtful one-ups and cold gambits,” per writer Gary Suarez. More than that, too, Shrapknel is a clinic in writing and ritual. From the first moments of Shrapknel, it becomes apparent the duo’s 2019 EP Cobalt was merely a delectable appetizer. Of course, Backwoodz-affiliate Willie Green also did additional production on Shrapknel, as well as mixed and mastered the record, making it a full family affair. Shrapknel was conceived when Prem moved a desk into a flush of sunlight and began writing to ELUCID beats. He quickly realized his long-time friend Curly Castro also had some ELUCID beats in his harddrive. Why not, they thought, come together and yarl over these productions as one?

“I was in a weird spot artistically, where I was going through what the next move was gonna be,” Prem tells me. “I remember reaching out to ELUCID, and I was taken aback by his development as a producer. He had done a remix for me [‘Berlin’], a long time ago, 2015, for a project called Who Art in Nada. He gave me a crazy-awesome disjointed remix. A couple years later, I was like, ‘I wonder if he’s got beats.’ He sent me a whole folder. I got wind Castro had also gotten a folder, and I had hit a wall with what I wanted to do. I was like, ‘I wonder if he’d be willing to combine these beats and see what happens.’”

What happened was magic. Pure, hip-hop magic. Shrapknel is proof of the importance of working with someone you revere. Every second of the album standout, “Fashion Week,” is thrilling and free-flowing. Castro and Prem melt into each other, almost becoming one booming vocal, coiling around us. There’s a hunger and ferocity to their combined deliveries, but we’re free of desperation. There’s an effortlessness to these bars, as if they aren’t plumbing depths, but tapping an overflow of creativity for our listening pleasure. The subtle humor of “complimentary bellinis” fades into a clutching static, which propels us into the distorted “Beset.” The entire album moves this thoughtfully, feeding itself and us until we leave satisfied, rap-head gluttons.

“His writing,” Castro waxes when I ask him what he admires about PremRock. “I don’t know where he goes, but I just love what he comes back with. He just seems like a very high-brow writer. He reads a lot, he observes a lot, and he’s able to transfer it to lyrics. I’m always impressed with what he comes [up] with; Prem is very unpredictable. But you know it’s gonna be dope. Silver-tongued flow. I always call him Hemmingway on dope, dope in the hip-hop sense.”

I pose the same question to Prem, who tells me: “[Castro] is the most natural rapper I’ve ever met. Certain people are meant to do what they’re meant to do, and he’s meant to rap. He’s unbridled support. In no way is that a detraction of his skill. He removes his ego entirely when it comes to what he likes, and that’s super pure and hard to find. He reaches levels I have always aspired to reach, in terms of the art of rapping. I could sit and write and stress over one line and not be able to deliver it accurately. Watching him, it made me loosen the vice grips. I’ve never rooted for anyone as hard as I root for him, not to get all sappy on you.”

The duo’s intense reverence for each other makes the music sound all the better. As Castro explains it, he did not want to be a rapper when he first got into hip-hop—he wanted to be a hypeman. He wanted to big up his homies and watch them shine. He considers himself an enhancement to Prem, a perfect partner in that he wants to ensure the world hears Prem’s incredible flows and openness on the mic. Of course, in his quest to support PremRock to the best of his abilities, Curly Castro also sharpens his blade as a rapper.

“The essence of collaboration is the reason ShrapKnel sounds the way it does; I have to come correct,” Castro says. “As much as I praise Prem, he ain’t gon’ rock me on a track. Even if I’m setting the table, right? I’mma set a pristine table. Soup spoons and little forks and different knives. It’s gonna be set.”

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Part of setting the ShrapKnel table is our dear friend and production maestro ELUCID. Not simply part of the ShrapKnel legend, ELUCID’s beats push both Castro and Prem to be better writers. “The greatest thing about ELUCID—and all of us agree—we don’t know what he’s doing, but we don’t wanna know,” Castro details. “I never wanna see his setup. I never wanna see him make a beat. I want the mysticism and the alchemy and wizardry to be his. Anytime I ask him for a beat pack, anything could be in it. I just love [that] his palate is open. He has his own sense of timing, his own clock. ELUCID produces with a Dali clock. He’s not following time and space. He can go somewhere—like Prem—and come back with something incredible. ELUCID is making us all better. It takes us all to this other place.”

In this “other place,” PremRock produces work unlike anything from his solo catalog. “It pulls an attitude out of me,” Prem explains of the ShrapKnel projects. “Fresh Kils, who is my partner in a lot of ways, I’ll go to Toronto ever so often, and we’ll have one night where we drink and play each other music. I played him Shrapknel, and he’s like, ‘There’s such intense defiance about this record, and about you, too.’ I agree. It’s everything I loved about rap music as a younger artist. It’s Castro; it’s the ELUCID beats. It’s re-identity. It’s not necessarily a PremRock project; it’s this. It just created a lot more freedom to express.”

With this in mind, I ask Castro how the writing for ShrapKnel differs from his solo material. He explains the essential difference is having another body in the room. For his solo work, Castro prefers isolation for much of the process. But for Shrapknel, he trained up to New York to see Prem as often as he could, pulling crazy all-night sessions to produce the most and best material possible for the album. As Castro tells it, there’s simply different energy when you’re sharing space with your creative partner, something you can’t capture in emails.

“When you’re writing solo, you’re just bouncing ideas off yourself,” Castro says. “You’re asking existential questions: ‘Is this even worth going forward with a song?’ But when you have a partner, they can tell you right then, ‘Oh, let’s just drop it.’ The essence of collaboration can help you get your blade sharpened in a more efficient manner.”

Efficiency and the natural drive of being in a duo pushed both Castro and Prem to bring their best to Shrapknel. I asked them both separately, which verse was the most challenging to write, considering they had to share space with the other MC. Castro tells me: “To try to keep up with Prem? ‘In Dependence.’ He had that concept already tossed out; when we started that, he had four bars immediately. I had to catch up. It’s a great concept about addiction, and I had to relate. I tried to do more personal aspects of drug exposure I had in the ‘80s. That one was pretty challenging.” For Prem, the answer was simply: “‘86 to ‘96 Probably.”

Funnily enough, later on in my conversation with PremRock, he revealed Castro’s writing on “In Dependence” struck him so, he went back and “altered and doctored” his verse to match Castro’s incredible showing. If anything, these admissions simply prove how in lockstep ShrapKnel are. At two different points, too, the duo referenced the act of writing and inspiration. First, Castro told me the importance of being able to write on the spot, because, of course, JAY-Z could be calling at any moment.

“I always had this idea of the JAY-Z elevator pitch,” Castro explains. “A lot of times, people write, and they wait for a muse and some sprite to land on their shoulders and inspire them. While that’s all well and good, if JAY-Z calls you to the studio and he needs something right then, you can’t say, ‘I need the beat, I’ll call you back tomorrow.’ You gotta do it right then.

“With Shrapknel, because we had short writing time—I could be there for a day and a half, and go back to Philly—we were doing all these crazy all-nighters. I had to sit there and write. Whether I had inspiration or the halo of the great writers that came before me landed on my head, that ain’t matter. We had to produce in the time that was allotted. Being able to write on the spot, push your creative gene, was important when it came to Shrapknel.”

As for Prem, we took some time to relate on the importance of writing through the moments where you don’t want to write. It’s the best advice he’s ever given, in terms of writing: “Writers write.”

“My third old fashioned in, I’ll take on the position of the old sage, like, ‘This is what you need to do!’” Prem begins, “I always tell younger people they’re not always gonna be inspired. You’re gonna have to write through times where you don’t want to. This is advice I got when I was 23, 24: ‘If you’re gonna be a writer, you gotta write.’ I always took away: Writers write. You have to write, regardless of what [is going on]. Your craft is writing, so you should write. I know that sounds super reductive, but I try to do something every day.”

Dedicated to craft and always pushing and supporting each other, ShrapKnel is everything I meant to write about all those years ago, and more. They are the perfect rap duo for they are in each other’s heads, and decidedly comfortable telling the other when they need to step away from the process and start fresh. Curly Castro and PremRock pull an incredible attitude and irreverence out of each other on wax, something that feels timeless but is absolutely of the moment. As the world burns down and pandemics take hold, at least we have ShrapKnel to remind us of the precious things.


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