Bjork’s phenomenal trajectory has been utterly uncompromising and truly visionary. There's no debating that. On paper, it may look as though Bjork is shunning commerciality and moving forward musically with her gimmicky new album, Medulla, which purports to eschew the use of traditional instrumentation in favor of using the human voice to create all of the sounds and melodies, but by limiting herself and her musical landscape so drastically she ends up compromising her art and the trust of her fans for the very first time.

Medulla is a sub-par Bjork album, despite its ballsy risk-taking; it sounds unfinished and half-baked. It’s the first album in which she has obviously digressed. I understand and respect her need to push new boundaries as her career develops, but stripping her sound of its lifeblood is self-defeating to the point of irrelevance. While the concept of building an entire album around the human voice sounds intriguing, it does not translate well here consistently enough. Bjork’s voice is unparalleled in pop music to be sure, but it is not an instrument of limitless capabilities.

This idea has been executed before- just not in such a commercial arena. But Bjork's commercial arena is sure to shrink as a result of such an experiment (I can only imagine the bewildered suits at Elektra trying to pick out a single). Notable world musicians like Sheila Chandra and Nusrat Fateh Ali Khan have both played on similar voice-only themes, but they have stunning, mellifluous voices that work beyond mere human emotion to evoke sounds unfamiliar to Western ideas of music. Bjork's stuttered, guttural cadence is too recognizable to disguise itself as merely an instrument.

On Medulla's fifth song, "Oll Birtan", Bjork attempts to fulfill the promise of such an unorthodox musical venture. Diverging vocal tracks swarm around Bjork's languid melody in stark, syncopated rhythms, and it lulls you into the dense atmosphere of Bjork's isolated fantasyland. "Who Is It" is the only song with even the remotest potential to be a single. Or maybe it's the fact that it's the first song on Medulla that has a proper beat. Either way, it's classic Bjork: relentless vocal overdubs support an explosive melodic phrase, blurted out with Bjork's strange enunciations.

Medulla is too caught up in its adherence to its theme to be heralded as a success. Some of these songs beg for proper instrumentation. As it is, the songs feel stymied, limbless and muted.