Seven years after Sleep’s demise, Al Cisneros and Chris Hakius return in a pared-down bass-drums-vocals configuration. Although jettisoning guitars might be deemed sacrilegious by metal purists, Om doesn’t sacrifice any of Sleep’s lumbering, Sabbath-weight riffage as Cisneros’s distorted, fuzzed-out bass does the job admirably. The name Om corresponds perfectly with the pair’s mantric, minimalist style. Sleep buried listeners under tons of sonic magma, the ideal soundtrack to stoned, navel-gazing stupor; by contrast, Om’s hypnotic groove aspires to a higher state, suggesting a heavy yet ascetic regime of meditation. Variations on a Theme’s transcendental design manifests itself in the sonic architecture. The song remains the same across these three crawling numbers (essentially movements in one gargantuan, ritualistic piece), throughout which the duo builds repetitive, mesmeric patterns: Cisneros grinds out meandering, python-thick basslines while Hakius pounds an earthmoving beat punctuated with precise, ringing, cymbal-strikes like the tolling of some primal ceremonial bell. Cisneros’s unique sung-chanted vocals are another key element of this ritual as he intones quasi-mystical fragments in a clipped, affectless manner. Often ignoring standard syntactical rules, his lyrics are largely impenetrable and could be cryptic crossword clues or an esoteric sacred text run through beta-version translation software. The imagery emphasizes flight, ascent, elemental forces, and liberation, and Cisneros’s abstruse idiom is rich in decidedly un-rock terms like “elliptic,” “effulgent,” “hierophant,” “anchorite,” “choric,” “attenuate,” “Vedic,” and “centripedal.” “Smoke on the Water” this isn’t. However, the literal meaning is irrelevant — it’s all about the overall effect: bridging the ancient and the timeless, Om seems to be channeling something of mythical, cosmic proportions. The sheer strangeness stops it from sounding like new age nonsense, which in others hands it easily could be. Traditionally, metal hasn’t been known for artistic adventurousness but judging by this reimagining of the genre’s fundamental components, Om is unafraid to investigate new possibilities. – Wilson Neate