Folk Singer is like a good mystery: What’s on the page might draw you in, but it’s what isn’t that keeps you going. Released in 1964, Folk Singer marked Muddy Waters’ first all-acoustic album—an experiment, in part, in trying to market him to a broader, whiter audience. While his early music released the energy that helped form rock ’n’ roll, Folk Singer was subtle and restrained, an exercise in negative space. You never sense him swinging for the fences or pouring it all out. If anything, the album’s most dramatic moments are its quietest ones (“My Captain,” “Long Distance,” “Country Boy”). And even when the music picks up—“Good Morning Little Schoolgirl”—the mood has a spectral quality more redolent of country blues than of Waters’ electric strut. He says he’s after the schoolgirl—but it sounds like he’s singing to the moon. At the time he recorded Folk Singer, Waters was riding a wave of interest, thanks in part to artists like The Rolling Stones and Cream, who’d helped repurpose electric blues as something like pop. At the same time, promoters and record labels were trying to market artists like Waters not just as entertainers, but as stewards of a unique American tradition that, like jazz, deserved serious attention and institutional respect. The subtext here was clear: Blues was Black and low-class. But an album like Folk Singer, especially in the era of Bob Dylan, was a figure of cultural repute. Four years earlier, Waters’ label had gone so far as to photograph him holding an acoustic guitar for the cover of his live album At Newport 1960—even though he’d played an electric one at the show. Folk Singer not only accepted the gambit and beat the odds, but stands as one of the more singular blues albums of the post rock ’n’ roll era. Good poets know that words matter—but so do the spaces in between.