Jeff Buckley would have slayed on American Idol. We know this because Leonard Cohen’s “Hallelujah” has become such a mainstay among TV singing contestants hoping to show off their virtuosic powers, and because nobody sang it better than Buckley. The song, originally released by Cohen in 1984, made its way to Buckley via John Cale’s 1991 cover version, which traded Cohen’s baritone deadpan and synthesized soul for piano arpeggios and annunciated dramatic flair. Buckley furthered that evolution, swapping out Cale’s reverent piano parts in favor of finger-plucked guitar figures that sound like his fingers gently coursing up and down a lover’s spine. It’s magnificent guitar work, flirtatiously pretty enough that it could probably stand alone as an instrumental. The voice, though, is the main attraction. Buckley imbued Cohen’s smirking lyrics with a deadly serious blend of reverie, agony, and lust, stretching from somber sighing whisper to earth-shaking cry with the same operatic flair he brought to every performance. He rarely lets it rip, opting mostly to let his celestially endowed esophagus emote with understated restraint. He doesn’t even break into his trademark falsetto. In those climactic moments when he does raise his voice, when the sensations he’s been holding at a simmer finally bubble up into a boil, the line between pleasure and pain is eradicated along with everything else; there is nothing left in the universe besides Buckley’s bleeding heart. It was an undeniably beautiful performance, enough to make “Hallelujah” a standard, and it stands as Buckley’s most iconic moment. It’s also the centerpiece of Grace, Buckley’s breathtaking debut album, which turns 20 years old tomorrow.

Grace was the only album Buckley released in his lifetime, yet if you load up his discography on Spotify you have to scroll through eight other releases to get to it. There are live releases, an EP anthology, a collection of radio sessions, and several sets of unreleased scraps — any excuse to hear more of that voice. Buckley drowned in 1997 after taking a dip in the Wolf River with his clothes on and getting caught in the wake of a passing ship, and like many musicians who died young, his legendary status has increased exponentially in his absence. Still, Buckley is not some Nick Drake character whose genius remained in obscurity until after he passed out of this world. His talents were widely celebrated when he was alive, both by those who inspired him (Robert Plant, whose wanton wailing was a clear precursor to Buckley’s more refined emoting) and those he inspired (Thom Yorke, who cited Buckley’s influence on his own “Fake Plastic Trees” vocal take). His voice, so cataclysmic yet unimaginably delicate when he scaled it back, made him world-renowned.

Grace is a timeless showcase of that power. Again and again, he hummingbird-hovers over some string-laden sweep, then erupts into howling, growling, sensuality when the music gets bombastic — that, or he bellows seductively on a bed of spare ethereal guitar, or he roars exquisitely in moments of instrumental tumult, or he lifts his quivering falsetto back to the clouds from whence it came. But for all its awe-inspiring vocal performances, Grace offers more than that. Buckley’s most famous song is a cover, yet his songwriting was nearly as stellar as his singing. Structurally, the music on Grace mirrors his voice’s gorgeous flailing, often shifting from quiet, almost improvisational trembling to full-bodied rock songs with steady rhythms. It’s wildly unique and insanely dynamic. The twists and turns of opener “Mojo Pin,” for instance, expertly mimic the building tension and release of a sexual encounter; “So Real” pulls off the same trick without ever feeling like a retread. Buckley’s guitar playing throughout the album is nearly as memorable as his vocal takes — the riffs rippling through “Grace,” the gnarly chord changes undergirding “Last Goodbye,” the surprisingly ballsy hard-rock flourishes of the Soundgarden-esque “Eternal Life.” He was a longtime session player and the son of storied songwriter Tim Buckley, and both those legacies are reflected in Grace’s smart construction and wild flights of instrumental prowess.

Buckley’s lasting legacy is that voice, a divine power that he harnessed and whipped around like some superhero with a killer haircut. Yorke wasn’t the only one to imitate it; there’s an entire school of (mostly British) vocalists who owe their careers to Buckley, including but not limited to Chris Martin, Matthew Bellamy, Fran Healy, and that guy from Ours. Grace is a fine time capsule of Buckley’s tremendous singing ability, but beyond that, it’s a portrait of a well-rounded artist brimming with inspiration. When we lost him in 1997, we lost not only countless stirring vocal performances but many albums’ worth of unwritten songs. Maybe he never would have conjured the same charisma again, and Grace would still stand as his best and brightest offering to history, or maybe he would have given us masterpiece after masterpiece. We’ll never know. The one album he did leave us is still good enough to elicit chills two decades later. It remains a vast personal universe to be explored. There’s nothing else quite like it — so real, so raw, so gorgeous.