Three years after the a cappella Medulla, Bjork is ready to bring the beats back. On her latest disc, Volta, the experimental Icelander collaborated with everyone from British producer Mark Bell and Konono No. 1 to the beat-master himself, Timbaland.

Bjork imagines a wave of people destroying the White House on lead-off track, “Earth Intruders”: “The human race, we are a tribe….” she notes. “So let’s just march.” Everything from Timbaland’s marching tribal beats to Konono No. 1’s thumb piano can be heard on this raucous, technofied Planet of the Apes-like song.

Activism aside, the majority of Volta’s songs revolve around themes of love and motherhood, requiring a 10-piece all-female brass ensemble and the acoustic drumming of Chris Corsano or Lightning Bolt’s Brian Chippendale. But even the enigmatic voice of Antony from Antony and the Johnsons can’t save “My Juvenile” and “The Dull Flame of Desire” from sounding like their descriptive titles.

On the pretty, Chinese pipa-laden “I See Who You Are,” Bjork reminds us to celebrate the moment “while there’s flesh on our bones,” and Toumani Diabate’s sensual-sounding kora offsets the solemn topic of a pregnant Palestinian suicide-bomber on “Hope.”

Yet it seems as if the former Sugarcubes’ front woman is at her best on the more boisterous tunes like the Mark Bell-produced, Nine Inch Nails-esque “Declare Independence” when she repeatedly yells, “Declare Independence”/“Don’t Let Them Do That to You”/“Make Your Own Flag”/“Raise Your Flag!”

The princess of eccentricity herself deems 2001’sVespertine more nocturnal and celestial than her latest earthy effort. And the dreamy track, “Wanderlust,” a highlight of the unstructured Volta, is definitely more airy than grounded in its “relentless restlessness.” With most of her newest songs droning over five minutes long, Bjork might do better taking notes from her punk past, but, as she sadly proclaims on “Wanderlust”: “I have lost my origin, and I don’t want to find it again.”