“Clouds came in / Pushing through a window open to the wind.” Those are the first haunting lines of “Confusion,” one of the standout tracks on School Of Seven Bells‘ new SVIIB, sung in an icy whisper by Alejandra Deheza. It’s a delicate song, serene and full of ethereal synths, but it belies the roiling turmoil just below its surface. As Deheza recently revealed, “Confusion” was the final song she wrote with the duo’s other half, singer and multi-instrumentalist Benjamin Curtis, while he was undergoing treatment for cancer in 2013 — treatment that ultimately couldn’t keep Curtis alive. Throughout the song, the pain is palpable.

Few bands know in advance exactly what their last album will be. For School Of Seven Bells, there’s no question; SVIIB, the group’s fourth full-length, is its swan song. Curtis’ death three years ago at 35 — after a yearlong battle with a rare form of lymphoma — has sealed School Of Seven Bells’ fate, leaving a body of work that transcends synth-pop by reaching higher, deeper and broader. SVIIB is the duo’s crowning achievement. Shadowed by death and encased in digital production, it’s nonetheless warm and beautiful.

Deheza and Curtis began as musical collaborators before becoming romantically involved, a relationship that eventually reverted to a creative friendship before Curtis fell ill. That tumultuous bundle of emotion echoes throughout SVIIB. Deheza was left to complete much of the album alone, and loneliness permeates every moment — even the disc’s most dance-friendly track, “Signals,” an electro workout that shivers from a chilly distance. “On My Heart” is a heartsick tug-of-war summed up in the lines, “There was a you before me / There was a me before you.” Love, like the act of making music together, is never simple; Deheza and Curtis wrap up that complexity in immaculate, hook-filled bursts like “Awake,” with its sleek harmonies and retro-Eurythmics pulse.

In spite of its backstory, SVIIB is by no means mired in gloom. Its melancholy, reflective undertow is kept at bay by the elegance and brightness of songs such as “This Is Our Time,” with its assurance that “We are free to dream” — a statement that might sound hollow in another context, but here gets delivered with a bittersweet edge. “It kept you sane through the heartache and the pain,” Deheza sings in “Open Your Eyes,” a soaring pop anthem filtered through unimaginable grief. Tragedy may loom large over SVIIB, but the album is as much about acceptance, redemption and the solace of memory as it is about loss.

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