El-P and Killer Mike release their third album as Run The Jewels. (Run The Jewels/Run The Jewels)

When rapper-producer El-P and rapper’s rapper Killer Mike first collaborated, the alliance was mutually beneficial. They joined forces for Killer Mike’s “R.A.P. Music,” his sixth solo album, where El-P returned to his strength of creating tracks with a more traditional hip-hop sound and Killer Mike (already a decade into his solo career) was finally provided a sonic backdrop worthy of his explosive lyricism. The following year they formed Run the Jewels, a supergroup that brought El-P out from behind the boards to rap, too. The success that followed was a testament to both the strength in numbers and the power of rebranding.

Fast-forward to today. Run the Jewels has released its third album in almost as many years. Together, they’ve developed a major cult following that has paid off for them collectively and individually. Killer Mike’s newly raised profile has allowed him to moonlight as a political pundit on HBO and CNN, including a campaign season run as one of Bernie Sanders’s most visible surrogates. And in 2015, El-P worked with noted Hollywood film composer Marco Beltrami on the “Fantastic Four” soundtrack.

Their collaboration has also meant compromise. On their first two albums, both rappers embraced a charming bad-guy persona at the expense of their most endearing qualities — Killer Mike as an introspective and empathetic storyteller, El-P as a cryptic forecaster of all things apocalyptic. What they settled for, by and large, was an aggressive brand of aimless braggadocio. This isn’t a bad idea in itself; hip-hop could stand a few more supervillains. But as rappers, they’ve never had much in the way of natural chemistry. And at times it can seem as if, instead of feeding off each other’s energy, they’re only waiting their turn at the mic. The new “Run the Jewels 3,” is their most effective work, in part because it at least gives the illusion that they’re speaking to each other rather than shouting at the listener. After being joined at the hip for the past three years, they seem to be more in sync now than ever.

On “Oh Mama,” they trade lines back-and-forth with near-seamless transitions over a hard, wobbly beat that harks back to El-P’s seminal work in the early 2000s. Over the frantic march of “Panther Like a Panther,” featuring Miami rapper Trina on its infectious hook, they rhyme at a headlong pace without ever losing sight of the fact that it’s a collaboration and not a competition. And on “Everybody Stay Calm,” which sounds like something out of a John Carpenter flick, Killer Mike offers his partner in rhyme a bit of friendly advice: “Hey El! The AR’s an option for any a------ wanna talk and pop s---.” It’s all tongue-and-cheek, but he says it with an air of camaraderie that doesn’t feel forced or manufactured.

The weaker moments of the album suffer from some of the same shortcomings that plagued the duo’s previous efforts. Songs with more experimental and abrasive production, like “Hey Kids,” “Call Ticketron” and “Legend Has It,” are sonically interesting but also feel a little exhausting, dragging on like an unnecessarily long car chase scene. So while Run the Jewels has made significant strides toward becoming a convincing rap group, it still has a tendency to sound like two solo artists mashed together.

The art of collaboration — especially in hip-hop — is a tricky thing. Supergroups rarely make good on lofty, if not impossible, expectations. Still, with talents as impressive as Killer Mike and El-P, even their misfires are likely to give off sparks.

Run the Jewels will be in concert at Echostage on Jan. 12. Tickets are $35. echostage.com.