Little Shalimar The unheralded behind-the-scenes star of the show, Little Shalimar snags co-production status on about half of the album's tracks, along with adding guitar and synth licks to "Blockbuster Night Part 1." Don't sleep on Lil' Sha's skills.
Wilder Zoby Brooklyn-based Wilder Zoby contributes keys work on Run the Jewels 2's opening and closing cuts, along with a production assist on the razor-sharp "Oh My Darling Don't Cry." To dip into the man's own vault, check out 2013's lothario-esque "Contagious," itself co-produced by El-Producto.
Michael Winslow Yep, the world's finest beat-boxing Police Academy graduate is the voice behind the robotic refrain on "Oh My Darling Don't Cry."
Diane Coffee A former member of indie rocksters Foxygen, Shaun Fleming now records as Diane Coffee and released his own debut album last year. Titled My Friend Fish, it was spearheaded by the woozy and wistful single "Green." Fleming's vocals and piano work can also be heard on RTJ2's "Crown."
Smoota Hip-hop's most important trombone riff of 2014 goes to Smoota, whose brass work forms part of the opening cut "Jeopardy." Check out the man's Fetishes album from last year for more of his often salacious ditties. Zack De La Rocha Given the task of closing out the ferocious "Close Your Eyes (And Count to Fuck)," the Rage Against the Machine man puts in a Run the Jewels-worthy turn. Although at times his voice somewhat resembles '91-era Queen Latifah (not a slight).
Isaiah Owens "Angel Duster" is Run the Jewels 2's dramatic endnote. Part of the song's climactic appeal comes from the keys woven into the fabric of the production. Those notes are the tinkerings of Isaiah Owens, whose prior musical dalliances include the Mars Volta and Jack White.
Gangsta Boo The potty-mouthed Southern chanteuse is the one applauding her man for making a porno tape on "Love Again."
Travis Barker Make room for the funky drummer, this time with former Blink-182 and Transplants sticksman Travis Barker being responsible for the percussive heart of "All Due Respect." When not galavanting with Run the Jewels, Barker spends his spare time laying down-drum patterns for rap kids like Yelawolf and Hopsin.
James McNew A Yo La Tengo mainstay, James McNew broadened his bass chops to include contributing additional, brooding low-end noise on "Early."
BOOTS Consider BOOTS Run the Jewel's official Beyoncé connect, being that the often mysterious Jordy Asher contributed production and background vocal work to her 2013 long-player. The man's own fervent track "Dust" will give you a taste of his solo styles, while he notches a RTJ cameo on "Early."
Matt Sweeney Album midpoint "All My Life" is an eerie, crawling number that weaves in additional guitar work from Matt Sweeney as the track progresses. Beyond his Run the Jewels tryst, Sweeney's vault of collaboration goes deep: He's also been involved in projects from Guided by Voices, Cat Power and Probot, and notched an early rap credit on Cage's "Good Morning." Respect the man's résumé.
Trackstar the DJ The unofficial third member of Run the Jewels -- and once upon a time an important staple in the St. Louis hip-hop scene as well -- Trackstar holds down tour DJ duties along with adding scratches to "Blockbuster Night Part 1" and "Close Your Eyes (And Count to Fuck)." For a savvy summation of the man's skills, peep his mixtape tribute to No ID.
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