Long-known for their relatively epic waits between studio releases, the Beastie Boys surprised fans this spring with the announcement that their new record would arrive a scant three years after 2004'

Long-known for their relatively epic waits between studio releases, the Beastie Boys surprised fans this spring with the announcement that their new record would arrive a scant three years after 2004's "To the 5 Boroughs." But the Beastie Boys are also long-known for sudden stylistic left turns, and shortly thereafter, they revealed the album would be comprised solely of instrumentals.

As promised, "The Mix-Up," due this weel via Capitol, goes heavy on the groove, especially the splashing, crashing Meters-inflected funk the band has been consistently serving up since 1992's "Check Your Head." But there's not a rhyme to be found.

"If we were trying to maximize our demographic or whatever, I'm not sure we'd come with an instrumental record right now," says Michael "Mike D" Diamond, whose bad self runs things on the drum kit throughout the album. "But I think we have to give people who've been listening to us some credit. They've gone to different places with us already, in terms of the influences we bring to the music we make, so hopefully they'll be able to hang with this curveball as well."

The curveball began taking shape about a year or so after "To the 5 Boroughs" was released. "With '5 Boroughs,' we were each working on beats, sitting in front of our laptops and samplers," Diamond says. "This time, we thought, 'Let's do a 180 from that, and sit down and play some instrumentals and see what happens that way.' We just didn't really stop until we finished."