Just before Valentine’s Day in 1983, Prince released “Little Red Corvette,” which eventually peaked at No. 6 on the Hot 100, his first single to end up higher on the general chart than the R&B one. Eighteen months later, he would become one of the biggest pop stars in the world, an artist made more mysterious by their fame. During sessions that lasted from December 1983 to April 1984, Prince finished Purple Rain, put together incidental music for the film, laid down the bulk of the Time’s Ice Cream Castle and the Apollonia 6 album, and recorded Sheila E’s The Glamorous Life, somehow without collapsing against the studio console. His songwriting was a glistening machine, animated by inner tensions.

When some musicians die, their record company grasps for whatever material remains, like a medieval saint parceled out into increasingly meager relics. Prince left behind the inverse problem: Thousands of unreleased tracks with no suggestion for how to handle them. So far, his estate has treated that music with care; an expansive reissue of Purple Rain came out last year, but Piano & a Microphone 1983 is the first posthumous album culled entirely from Prince’s vault. Instead of piecing together one of the many projects he envisioned and abandoned, the executors found a session from Prince’s home studio, recorded to cassette in a single take; now and then you can hear him sniffling. Alone with his piano, Prince sounds unusually relaxed, mindful of the contradictions that always seized him yet willing to imagine their reconciliation.

At the beginning of Piano & a Microphone, Prince asks his engineer: “Is that my echo?” Opening track “17 Days” would later become a moody dance number, the B-side of “When Doves Cry,” whose two repeated chords seem to be scraping across the ocean floor. The sketch heard here is much looser, syncopated by a tapping foot; Prince embellishes the notes as if tugging at a frayed thread. It throws the forlorn precision of his lyrics into deeper isolation—the cigarette-counting narrator might only be talking to themselves. Later on, Prince runs through “Strange Relationship,” which wouldn’t surface until 1987’s Sign o’ the Times. The finished version marries a playful melody to alienated emotions: “Baby I just can’t stand to see you happy/More than that, I hate to see you sad.” On Piano & a Microphone, the vocal dissolves entirely, as Prince strangles his own words.

Several tracks from the cassette practice grander gestures still to come. Prince so admired Joni Mitchell that he flew her out to the premiere of his film Under the Cherry Moon on a private jet; covering “A Case of You,” his falsetto swallowed the phrase “holy wine” with reverent despair. The Piano & a Microphone recording is much shorter, barely 90 seconds long, but you can tell he returned to her song over and over again. It makes up a medley of sorts with “Purple Rain,” which is really a miniature, an idea of the “Purple Rain” that Prince would fashion from a live performance with the Revolution months later (their first time playing it in public). Hearing a fragment of that monumental song feels like coming across a sphinx’s head in the desert wastes.

The “new” material on Piano & a Microphone has already circulated as bootlegs, but this album clarifies its details, rescues it from indistinct hiss. The most surprising moment is when Prince begins playing the gospel standard “Mary Don’t You Weep,” a song that must have been absent from all his potential tracklists, even ad-libbing fraught lyrics: “I don’t like no snow, no winter, no cold.” Fingers slinking over his piano with heavy steps, vocals slurring at the edges, he gives the spiritual a physical force. “There has always been a dichotomy in my music,” Prince once said. “I’m searching for a higher plane, but I want the most of being on earth.” Piano & a Microphone is both omen and artifact, a rehearsal for another life.