The mash-up approach has delivered diminishing returns since 2004, when Danger Mouse’s Beatles-Jay Z hybrid, The Grey Album, triggered an avalanche of lazy cut-and-paste laptop tweakers. It’s an art form with a discouraging shelf life, and the novelty has worn off. But Umphrey’s McGee rejuvenated the entire concept with Zonkey, an album of jolting genre cross-pollination that makes you notice the core similarities between Frank Zappa and Bob Marley, or Fleetwood Mac and the Weeknd. The progressive-jam sextet has showcased this strange skill onstage over the past decade, beginning with their regular Halloween spectaculars, but more nuances cut through in the studio. Rather than following the basic mash-up recipe—pairing one song’s hook with another’s riff or rhythm track—Umphrey’s rebuild these elements from the ground up, re-recording the material instead of sampling it. “Sweet Sunglasses” seamlessly shifts between two ‘80s synth-pop hits, Eurythmics’ “Sweet Dreams (Are Made of This)” and Corey Hart’s “Sunglasses at Night,” before interpolating the sizzling synth solo from MGMT’s indie-funk anthem “Electric Feel.” More thrilling is “National Loser Anthem,” which highlights the mutual brooding of Beck’s “Loser,” Radiohead’s “National Anthem” and Phil Collins’ “In the Air Tonight.” The band incorporates a wide spectrum of vocal and instrumental styles, veering from reggae to R&B to metal. (Check out drummer Kris Myers’ disturbingly spot-on James Hetfield grunts on Metallica-Gorillaz fusion “Sad Clint Eastwood.”) Throughout, they weave in elements of the original tracks, sprinklingin manic guitar and synth solos, but these flights of fancy always service the shapeshifting songs. With Zonkey, Umphrey’s not only makes the mash-up fun again—they’ve made it edgy.