No, that's not a typo in the title; Brooklyn's black-metal upstarts have grafted the Greek "ethica" onto the word "aesthetic." That unexpected, moralist signaling might be as subtle as a blast beat, but that's the objective here: Since they popped up in 2009, Liturgy have seemed most comfortable with their feet planted both within and without the genre tent — using various sonic attributes to suggest a "transcendentalist" way outside black metal's strict confines.
Frontman Hunter Hunt-Hendrix has published a short tract outlining his vision of "apocalyptic humanism," but you don't have to read the text to understand what he means. "Generation" makes the point as succinctly as anything else on Aesthethica, with its complex meter changes that, every so often, resolve into a syncopated glory worthy of a Boredoms sun-worship jam — one that counteracts the lunar fascinations of orthodox black metal with harmony patterns that suggest some kind of heaven-aiming finish line. (See also: the gradually additive vocal parts of "Glass Earth," which recall Steve Reich.)
Does that mean it's just crossover bait? Not quite. Aesthethica isn't a pander mission so much as an invitation to listeners more frequently found inhabiting other musical backwaters. Liturgy's simultaneous embrace and disrespect for black-metal conventions is reminiscent of the same revolution undertaken by American classical composers in reaction to the dogma of mid-century European complexity. When post-minimalists wanted to put pop harmonies back into their varied rhythmic structures, the result was dubbed Totalism — a phrase associated with the composer/critic Kyle Gann, whose son Bernard plays guitar in Liturgy. So now we have Totalist metal: a realm where catharsis, groove and hyper-intellectual structure cohere into something that can appeal beyond the kingdom of the underground. How unexpected. How inspiring. How metal.