Years before “Ain’t No Sunshine” made him an overnight star, Bill Withers and electronic-music pioneer Mort Garson cut a 45 that sounds like nothing either artist would do again.

The Bill Withers story usually begins in 1971 with “Ain’t No Sunshine,” the two-minute folk-soul masterpiece that sounded like nothing that came before it, yet somehow felt familiar as family the first time it was played. By the time Withers finally quit his job installing toilets in airplanes at age 33, he had a Grammy in his hands and the world at his feet. His flawless debut album, Just As I Am, announced a fully formed talent so individual, potent, and profound that he practically created his own genre — a unique style of plain-spoken (but powerfully sung) folk-soul that only continues to grow in its impact and influence. And most remarkably, Bill Withers seemed to come out of nowhere. Except, of course, he didn’t. What’s almost always overlooked in the “overnight sensation” legend of Bill Withers is the long-gone 45 he cut in 1967, a record worth checking out for a few very good reasons.

This was the first time we’d hear Bill Withers finding his voice as a songwriter and performer

First, of course, is the simple fact that it was the first time we’d hear a legend finding his voice as both a songwriter and performer. The single’s A-side is called “Three Nights And A Morning” but it’s really an early version of the song which—once stripped back, slowed down, and mellowed out—would become “Harlem,” the original A-side of the single that DJs flipped over to make the B-side, “Ain’t No Sunshine” a million-selling standard and Grammy winner. The lyrics are basically the same, but the psychotically frantic pace changes the song’s point-0f-view completely. Where “Harlem” sounds like Withers narrating a 125th Street weekend from his chilly apartment window, “Three Nights And A Morning” sounds like he’s square in the middle of the hip-folks’ all-night, out-of-sight party. When Withers closed his legendary (and absolutely essential) Carnegie Hall concert with “Harlem/Cold Baloney” he basically split the difference between the two versions of the song, but still didn’t approach the breathless velocity of “Three Nights And A Morning.”

Withers rips apart Irving Berlin’s “What’ll I Do” with such ferocity that it’s barely recognizable from any version that came before or after

Just like the “Harlem” single, its the B-side of “Three Nights In A Morning” that manages to eclipse the A-Side. That’s where Withers rips apart the ancient Irving Berlin song, “What’ll I Do,” with such ferocity that it’s barely recognizable from any version that came before (most notably, Frank Sinatra and Nat King Cole) or after it (quite notably, Bob Dylan and Willie Nelson, both of whom covered the song just this year). Sure, Withers’ version starts off sounding like he might just sing it straight, but it takes less than 30 seconds for Bill to yank the song from the Broadway stage to a storefront church and turn “What’ll I Do” from a soft, saloon-song lament to a full-throttle, go-go-soul rave-up. He didn’t do too many covers in his career — when you’re capable of writing songs like “Lean On Me,” “Use Me,” and “Grandma’s Hands,” why bother? — but the trick he pulls on “What’ll I Do” is one he’d do just as brilliantly on “Let It Be” and “Everybody’s Talkin’,” when he set gospel fire to those on his first album.

The other interesting thing to know about Bill Withers’ first 45 is that it was the work of producer Mort Garson, who, it must be noted, would later become an electronic music pioneer with one of the most bizarre discographies in 20th century music. He wrote, among other hits, “Our Day Will Come” which would be covered by everyone from Franki Valli to Amy Winehouse, worked as a producer and arranger for Glen Campbell and Mel Tormé, and seemed to be the go-to guy for square, adult easy-listening until he discovered the Moog synthesizer. Things got a little weird from there, with Garson releasing entire albums dedicated to the signs of the zodiac, a psychedelic satire of The Wizard Of Oz, music to help plants grow, as well as “electronic musical impressions of the occult.” Garson’s music was also heard during broadcasts of the 1969 moon landing and he even wrote the theme song to Beware! The Blob, the first and only film directed by Dallas/I Dream Of Jeannie star, Larry Hagman.

So it turns out this one-time collaboration between Mort Garson and Bill Withers wouldn’t sound like anything either artist would do again. And despite “Three Nights And A Morning” and “What’ll I Do” being the vital, rafter-shaking sounds of these two very different artists finding their voices, and despite the ever-expanding appreciation for Withers’ deft genius, this single has somehow gone unnoticed. Let it in your life.