Most progressive bands eventually reach a point where their fans will become divided for good. That one album where the band in question, who has been hinting at major stylistic change for some time, finally crosses a permanent threshold into a new sound, losing appreciation from some old fans while gaining attention from a new bunch in the process. Enslaved, whose lengthy track record is almost unmatched in quality and innovation, have reached this point with Vertebrae. The good news is that they’ve crossed over gracefully and have come out on the other side sounding as good as they always have.

Enslaved have been climbing steadily up the progression ladder to a more atmospheric style for several albums now, and with Vertebrae, find themselves even more far removed from their blackened past then they were after Ruun. So anyone wondering if these guys were going to start exploring more aggressive territory should think again. There’s much less of the thundering rhythms and aggressive tremolo riffs found in the last several albums, with more concentration on airy ethereal passages, post-rock influenced clean guitar figures, and layers of different instrumental textures. The multi-tracked clean vocals are much more prominent this time around, and even when Grutle falls back to his guttural screams, such as in the hypnotizing “Reflection,” the overall atmosphere is more tranquil and introspective than the band has ever sounded before.

Some may view this as an automatic step down from the balance of atmospherics with extreme metal heaviness so effectively conceived on albums like Below the Lights and Monumension, but make no mistake, Enslaved pull off this less aggressive style beautifully. The angular riffs, dense melodies, and trippy psychedelic tones are expertly constructed and without a shade of pretentiousness, delivered by tasteful but expressive musicianship and a smooth, organic mix that brings out all the little nuances that this band incorporates while keeping things clear and heavy.

The way these guys mix their unique instrumental textures with their spiritual vocal/lyrical approach, while still managing to come up with memorable and cohesive songs, is incredible. The spacey layers of keyboards and guitars contained in “Clouds,” the emotional vocals and riffage of “To The Coast,” the mathy chug and soaring melodic peaks of “Vertebrae”…it all sounds genuinely mystical, and straddles the line between fierce tension and swirling ambience like only Enslaved can. “Ground” ushers in some gorgeous acoustic strumming and distant, ethereal vocals that sound more than a little Pink Floydian, before launching into one of the album’s few guitar solos, a simplistic but stirring lead passage that closes the song in epic fashion. The thrashy black metal riff that opens “New Dawn” is perhaps the only moment on Vertebrae that feels out of place, but the guys quickly regroup with more of their shimmering melodies and unique instrumental interplay, rendering the track a winner after all. “The Watcher” wraps things up with a series of morose clean sections and energetic tremolo melodies, ending on a sudden and non-pompous note that perfectly suits the more loy-key nature of this release.

I can understand those who may miss the band’s more intense elements, but it's hard to argue that in terms of evoking emotion and building a unique atmosphere, Enslaved hit it out of the fucking park with this album. Its innovative mix of influences, perfect structuring, and indefinable aura stands up to anything the band has released thus far. This is likely to be the outfit's most divisive work to date, and even longtime fans may need to give this a while to sink in. But rest assured that these guys have lost absolutely none of their amazing artistic vision and incredibly musical ability in their journey to slightly calmer waters. While by no means flawless, Vertebrae is quite unlike any metal album I’ve ever heard before, and is a must-listen for veteran Enslaved fanatics and outsiders alike.