There is an excellent documentary about Stax Records where Hayes was a resident producer/writer/artist that shows his brilliant non-conformist career in sharp relief. The whole label was a kind of anti-Motown aesthetic and the documentary has a lot of footage from the Wattstax event. The whole label was one of the early totally self-determining efforts to crash through the White Order's recording business monolith ( and Stax was founded by a small clique of southern white folk! ). They had a brilliant recording formula that put the bass and drums/rhythm section on top of the mix which went against everyone else's production laws at the time. Hayes was one of the artists that took the label into outerspace as far as wide spread popularity goes. He really changed many later artist's approaches to recording.