He recorded facing the wall
Johnson, after learning to play the guitar from Zimmerman, moved from an amateur into a guitar-playing genius. He first worked as a traveling musician, playing on street corners and in juke joints in Mississippi before getting an opportunity to record in Texas in 1936, according to NPR. After the hit “Terraplane Blues”, he was called back for a second recording session but he died a year later at age 27.
Johnson remained largely forgotten until a re-release of his album “King of the Delta Blues Singers” in 1961.
Noted for hits like “Cross Road Blues,” “Me and the Devil Blues,” “Hellhound on My Trail,” and “Up Jumped the Devil”, Johnson, on his recordings, was “simultaneously playing a disjointed bass line on the low strings, rhythm on the middle strings, and lead on the treble strings while singing at the same time,” Eric Clapton recounted in his autobiography.
Interestingly, most of his recordings were done while facing the wall, creating a beautiful sound that set him apart from other blues-musicians of the time.
Elijah Wald, a musician and the author of the book Escaping the Delta: Robert Johnson and the Invention of the Blues, told NPR that Johnson, by facing the wall, “might have made his vocals sound better to a later generation accustomed to high fidelity.”