Cymbals Eat Guitars’ 2009 debut “Why There Are Mountains” was an indulgent patchwork of indie rock tropes—equal parts Arcade Fire’s chamber-pop pretensions, glam’s shiny haze, and Pavement’s quirky bitterness. The New York quartet begins its sophomore release “Lenses Alien” with the same mélange of garage-rock chords and glockenspiel tingles, but within minutes, opening track “Rifle Eyesight (Proper Name)” becomes the album’s densest noise-rock jam. Though it feels predominantly like an aggressive attempt to place distance between “Lenses Alien” and the band’s previous work, it also signals what is to come: with a stark instrumental palette and a penchant for cultivating restlessness, “Lenses Alien” binds together chaos and cohesiveness in a brilliantly charged opus.

The album runs wild with variation. The opening track continues from its thunderous jam into punchy noise pop, funereal piano chords, and, finally, an anthemic stomp. Tempo and tone shift ceaselessly on all the tracks. Some also touch lightly on the hallmarks of other styles, like the piano theme of “Secret Family,” which is reminiscent of Springsteen. The band eschews traditional song structures and conventions, and their stylistic dares range from opening songs with their most climactic strokes to introduce lyrics in only the last 30 seconds—as on the beautiful “The Current.” Of course, even that rule has its exceptions: the comparatively stable riff-chorus structures in “Shore Points” and “Wavelengths” almost create false senses of security between the bursts of anarchy.

But the band works most effectively on a smaller scale, as they almost constantly alter every instrumental line. Frontman Joseph D’Agostino often shifts his guitar melodies every few measures, re-sequencing the riffs’ notes or subbing in new high ones; drummer Matthew Miller continuously tweaks his beats, and he often reinterprets them in stellar drum fills. The complexity makes every track feel like a living and mutating composition, and the restless, incessant alterations breed anticipation that lingers over even the album’s slower passages.

The band unifies the album’s structural diversity in an instrumental palette of echoing lo-fi guitar, drums, smooth bass, and occasional soft piano. That common sound creates strong cohesiveness across the album, but also a pleasantly simple tone. Yet that simplicity also facilitates the album’s complexity—with such uncluttered tracks, the constant subtle shifts of each instrument become all the more perceptible. The intersection of restraint and exploration is the greatest triumph of “Lenses Alien”—the band’s ability to unravel fluidly infinite variations out of the same limited components, and to balance conflicting tones.

D’Agostino’s guitar landscapes dominate the album, and despite the occasional forays out of his genre, he mostly works in two styles: cyclical high-low patterns reminiscent of Robert Smith and Peter Buck and scraping garage-rock chords like J Mascis. His itinerant melodies’ hypnotic shifts leave little place for catchy hooks, and that lack actually aids the album’s feel—with nearly no hooks to anchor it, the album’s momentum continues in freefall, swiftly but securely.

The album’s lyrics embody a tension between the predictable and the unstable—in content as well as accessibility. D’Agostino threatens simple, grounded suburban imagery with artfully drawn cosmic speculations and touches of Lovecraftian terror, as when he sings “the roads, they are parabolas with nameless water towers near the exits / You turn it all on end and it still wouldn’t be taller than the biotic arch / At the crown of creation,” on “Definite Darkness.” But too often, he seems to focus more on singing passionately than on keeping his words comprehensible. Though it works, in a way—the intelligible lines establish the suburban and cosmic motifs, while the others’ elusiveness further defies coherence and stability—more comprehensible lyrics could have deepened and complicated the already lush album.

The group builds the record’s self-contrasting dynamic right through the end of the last track. D’Agostino releases his most fearsome scream at the end of closing track “Gary Condit,” a nails-on-chalkboard climax to the album’s manic energy. Then he abruptly cuts it off without so much as an echo, and the album ends immediately. Neither the chaos nor control held tightly in balance throughout finally claims the album, and the drama of that final clash embodies the duality that makes “Lenses Alien” one of the year’s most powerful releases.

—Staff writer Austin Siegmund-Broka can be reached at asiegemund-broka@college.harvard.edu.