Any band that can take Melville’s “Moby Dick” and make and album out of it commands respect.
In 2004, Mastodon did just that in “Leviathan,” with an unrelenting series of in-your-face riffs and forceful vocals that matched the power of the white whale.

Two years later, they took listeners into a brutal, hallucinogenic world with “Blood Mountain,” complete with a one-eyed Sasquatch that can see the future. Calling their latest effort “ambitious” doesn’t cut it anymore — “Crack the Skye” is out of this world, in theme and quality.

Mastodon picked up a new producer for their fourth album, Brendan O’Brien(Bruce Springsteen, AC/DC, Pearl Jam, Rage Against the Machine) and his mark is apparent. While Mastodon has been known to bridge the gap between the indy-rocker conceptualist and the more conservative, more tattooed metalheads — this record might leave the latter in the clouds.

Their new sound is apparent from the get-go with the first track, “Oblivion.” Gone are the days of slightly unintelligible lyrics, now guitarist/vocalist Brent Hinds howls with a seemingly effortless clarity, evoking a style comparable to Ozzy Osbourne’s. Hinds has gone as far harmonizing with other members producing a sound similar to System of a Down.

Brute force riffs the band is known for are forsaken for more prog-metal keyboard led cuts, similar to prog-rock legends Rush and Yes. It never feels too unfamiliar, but they’ve certainly evolved.

In the four-part centerpiece, “The Czar,” the band conjures up Russian visionary Rasputin to help deliver an 11 minute modern prog epic. Hinds and drummer Bran Dailor deliver haunting vocals before hammering it away in the second, more aggressive movement.

Hinds wrote most of the album after a head injury he sustained after the 2007 VMA’s, this track pulls listeners into the vertigo he was in. Listen with headphones, and be absorbed.

The final track, “The Last Baron” demands to be replayed over and over, and at 13 minutes, it hardly seems repetitive.

Commencing with soothing chords and banjo style picking, along with Hinds’ continued excellence outside of his usual guttural vocal range, it continues with a series of thumping, hairpin tempo shifts, ultimately roaring into an art-metal explosion of two guitars playing off each other in a gorgeous two minute solo.

“I’d guess they would say/We could set the world ablaze” howls Hinds several times in “The Last Baron.” I’d guess he’s right.