Pop can be a dirty and destructive concept comfortably at home in an often cruel genre.

Within it, not even the notoriously monotonous have it this bad: all those branded with the title of “forward-thinking artiste” practically have to reinvent the wheel with each additional artistic statement. Subtle ideas and tiny triumphs? Forget ’em – they’re automatically deemed disappointments that can only pale in comparison to all epic accomplishments prior.

At this point, Bizarro Björk can pretty much do whatever she wants. Even if it garners less praise or rakes in less dough, it still floats Ö artistically over the heads of her audiences. Unfortunately, it’s not the same for the ethereal Icelandic alien-woman’s pop persona, whose craft must involve engaging those for whom delicious immediacy is a virtue. That side, the one responsible for some of the most unique, pulsating pop moments of all time (see: 1995’s “Post”), has hardly resurfaced since. Instead, her work has grown increasingly introspective, replacing the youthfully schizophrenic, scream-along anthems that were once her trademark.

After a preceding album largely populated with Inuit throat singing, imagine the premature excitement when Björk hinted that sixth full-length release “Volta” would be a refreshing transition back to fun, full-bodied pop. Ah, that magic word. Her highly anticipated pairing with A-list beatmaster Timbaland, (in addition to an already stellar gathering of guest performers including Antony & The Johnsons vocalist Antony Hegarty, Congo-based trance musicians Konono No. 1, and Brian Chippendale, drummer for frenetic noise rockers Lightning

Bolt) only further sealed the deal.

It’s a damn shame, then, that “Volta” isn’t nearly as ridiculously groovy, or even all that poppy, as it looks on paper. Especially for a record supposedly meant to encourage our more feral sides, most of it seems to tread away from all refreshing notions of musical tribalism and more toward her recent bouts of plaintive pondering. Of course, Björk’s delivery is still dynamically eccentric, and her knack for majesty even in near-silence is unmistakable. It’s just that many of her best qualities have been undercut by a simplistic new direction that intends to unshackle but too often feels stunted.

“The Dull Flame of Desire”, featuring a hearty slice of Hegarty’s slow-burning soul, starts out strong with a beautiful brass melody but soon dissolves after nearly eight minutes of histrionic warbling so excessively repetitive that not even the duo’s lovely voices can redeem it. Songs like “I See Who You Are” and “Vertebrae by Vertebrae” suffer from a similar lack of “Volta’s” promised buoyancy, and when Björk tries to make up for it on tracks like “Declare Independence,” it’s almost too obnoxiously messy to tolerate.

Still, when it’s good, it’s really damn good. Opener “Earth Intruders” starts off seeming a tad too clunky and overstuffed, but the layers of marching drums and Björk’s familiar, unhinged wail (commanding all listeners to “feel the speed,” no less) prove to be some of the disc’s true get-hyped moments. “Innocence,” a standout Timbaland track, is also party-ready with its strangely seductive cough-squelch beats that get the blood furiously pumping (and seem just as home in a Missy Elliot song – believe it!).

Though not flawless, “Wanderlust” nearly achieves Björk’s thoughtfully assembled electronica of old. The song begins with boats bidding farewell to their harbors while she exclaims just how relentless her desire to drift out and away is – the result boasts an orchestral richness that many of “Volta’s” other, more skeletal moments lack.

OK, maybe Björk herself shouldn’t have lit the fire under our asses, getting us all hot and bothered with the promise of a return to form. But really, “Volta” isn’t that much of a crime, especially after a few devoted listens (and a dissolution of all that hype). Björk is, after all, the type of artist whose missteps are as essential to her journey as personal victories – even under a constant pressure to please, her unpredictable pop ventures are still more interesting than most.