In 1994, on an album called Minimal Nation, Detroit’s Robert Hood stripped Motor City funk to its bones. Most of its tracks were made of little more than lithe, swinging drum programming and solitary synth patches that glistened like oil slicks; it’s generally considered the origin point for what came to be known as minimal techno. In February of the same year, more than 4,000 miles away, a taciturn young Finn named Mika Vainio took an even sharper scalpel to the same ideas. His debut album, Metri, couldn’t be more skeletal if it were a laboratory specimen. Where there are drum machines, they merely thump and hiss; his custom-built tone generators glisten like icicles and roar like buzz bombs. If Hood’s album represented minimal techno’s ground zero, Vainio’s was its ground Ø.

Vainio would go on to become best known as one half of Pan Sonic, a duo (with Ilpo Väisänen) that, from the early 1990s until its dissolution in 2009, waged a scorched-earth campaign against electronic music’s staid conventions. But it was Vainio’s Ø alias—after a symbol signifying absence in a number of contexts, from math and geometry to linguistics—that would be his longest-running project, evolving from those brutalist techno origins to encompass a wide array of electronic techniques and soundscapes.

In addition to many solo and collaborative albums under his own name, Vainio released eight albums as Ø until 2017, when he plunged from a cliff in France. He had been at work on a ninth Ø album for three years at the time of his death. Working from notes he left behind, Tommi Grönlund, his friend and founder of the Sähkö label, and Rikke Lundgreen, Vainio’s former partner, compiled the material into Sysivalo, his final album. (According to Lundgreen, Vainio had already decided upon the album concept, title, track order, and even cover art.) The title—a portmanteau meaning something like “charcoal light”—is evocative and fitting. Vainio’s music often felt like an apocalyptic clash between being and nothingness, but on Sysivalo, darkness and light flow together in ways that are unusual for his work, evoking a dynamic mixture of vulnerability, tenderness, and grace.

Vainio’s music could sometimes sound like he had jacked directly into an electrical substation, but his palette here is soft and tufted. Distant thunder takes on a purplish pastel hue, misted with white noise. There are few hard attacks and even fewer moments where the levels bleed red. A bite-sized quality distinguishes these 20 tracks, which run shorter than he typically worked. Vainio’s enduring interest in capturing the vastness of sound is distilled into pieces that feel both atmospheric and tactile, like cupping small clouds of colored smoke in your hands. Yet there’s little doubt that Sysivalo is envisioned as an album—a single, overarching work, rather than a collection of stray pieces. A ruminative mood pervades the hour, and tones and themes frequently repeat. The drawn-out foghorn blast that opens the album with “Etude 1” reappears, whittled to a fine point, in “Etude 5,” and turns up again nine tracks later in “Aine” (“substance”), threading the album with a faint sense of deja vu.

The etudes that open the album establish the record’s pensive air. Shadowy rumbles dissipate into spectral shapes; pliable, chalky tones are ringed with a weird, metallic aura. The music is abstract and largely formless, yet the way sounds move through time—growing, morphing, decaying—gives it an unmistakable sense of purpose and direction. What seems at first like a dark, impenetrable palette quickly opens up to reveal a world of contrasts: now his tones are gaseous and floating, now they’re thick slabs of concrete.

Within these contrasts lie some of the most “musical” moments of Vainio’s career. “Etude 4” begins with what sounds like a punishingly low chord from Sunn O))), the drone-metal group of his friend and collaborator Stephen O’Malley. Then a clean-toned, lightly flanged guitar rises out of the murk, resembling something from the Cure at their gloomiest. In “Sylvannus,” we hear the doleful tones of what might be an actual synthesizer, not just buzzing electronics—a rarity for Vainio, and the contemplative melody it plays is even rarer.

On three tracks, he revisits his techno roots. “T-Bahn” (presumably a companion piece to “S-bahn” and “U-bahn,” from 2008’s Oleva) evokes Metri’s Millsian chimes and glowering bass throb, sounding at once heavier and more diaphanous than ever, and he returns to similar sounds several tracks later. The bass of “Dual” is so massive, it seems to suck the air out of the room; the reverberant squiggles of “Ursa” suggest wraiths lighting up the distant corners of a catacomb.

For all its intimidating scale and precision sonics, Vainio’s music was, first and foremost, an expressive vehicle, rather than a drily experimental practice. He drew his titles from metaphysics and science but also everyday events in his own life; the sleeve of his 2011 guitar album Life (…It Eats You Up)—with titles like “In Silence a Scream Takes a Heart,” “And Give Us Our Daily Humiliation,” and “Open Up and Bleed”—featured photographs taken after a drunken accident with a knife. Vainio suffered from alcoholism and depression; some of the stories shared by his family and friends are harrowing. But while it is certainly possible to hear much of his music as bleak or charged with negative energy, Sysivalo resists being reduced to one-dimensional readings. At times, there are moments of something that almost resembles hope.

“Kohtalo” (“destiny”) is among the quietest pieces in Vainio’s catalog, an 84-second miniature for unaccompanied music box. Toward the end, a dog barks in the distance. You can tell by the way its bark reverberates off nearby buildings that it is nighttime, probably a residential neighborhood in a European city—a scene of domestic stillness. It reminds me of something his father, Kalle Vainio, said of his son after he died. He recalled that Mika had once told him that he didn’t plan to start a family, given the demands of life on the road. “Mika’s autobiographical hints are very quiet, they are rarely underlined,” his father continued. “It is possible that some of his songs are lullabies for children whose father he could have been.”

“Loputon”—whose title translates as “endless”—closes the album with a startling sense of finality. It begins with a microtonal fog; the cloud clears, and bright, pinging tones drip down, an echo from his earliest records, as though in conversation with his younger self. The bass resembles a church organ; the pace is slow and ceremonial. The song comes to rest on a shimmering minor-key chord—the kind of ending that leaves no doubt that it is the finale—and the chord fades out, leaving only the sound of blowing wind. If, as Lundgreen says, Vainio finalized the track order before he died, then we know that he meant for “Loputon” to conclude the record. Nobody knows whether he intended Sysivalo as his final album. But “Loputon,” like the album as a whole, makes for a deeply moving swan song—a soft yet determined gleam holding fast against the darkness.