On their debut full-length, A Constant Sea, Brooklyn-based quartet Heliotropes extract all the doom from doom metal, all the sludge from sludge metal, and all the red-eyed confusion from stoner metal, and siphon it into an aloof and arid hybrid that lacks any metal impulses at all, retaining the weighty dread without sacrificing restraint in terms of volume or overstatement. Falling somewhere between the punishing guitar tones of doom metal's slickest shredders and the psyched-out wasteland of early drug-obsessed droners like Spacemen 3 and Opal, and bearing hints of the '90s Seattle grunge that followed, Heliotropes have made some of the heaviest indie rock available. The bar is set high right away, with rippers like "Psalms" offering churning riffs, overpoweringly drony solos, and vocal melodies with the same witchy timbre as Courtney Love's best Live Through This moments. Slow-burning tracks like "Ribbons" and "Good and Evil" feel like musical curses, deep trenches of droning rhythms forming a foundation for truly menacing vocals and murky outbursts of psych-tinged guitar. When the volume softens, the moods don't get any lighter. Acoustic tracks like "Unadorned" and "Everyone Else" highlight beautiful vocal harmonies from vocalists Jessica Numsuwankijkul and Amber Myers, but themes of heartbreak, emptiness, and betrayal keep things feeling bleak and distant even in the most intimate moments of A Constant Sea. These dark shadows can make the album somewhat impenetrable over the first few listens. Impressive amounts of musical control and devastating guitar production are instantly apparent, but also put a sheen on all the songs that makes them sound overly similar at first. Those who make it through the assault of riffs and overall detached feel of much of the record will be treated to obscured gems like "Christine," a near-perfect album closer that revisits moonlit '50s balladry through a Mazzy Star lens. Of course there's also a brutal fuzz solo in the middle, but that just makes the song an all the more fitting ending to a strongly inventive debut.