100 years after John Coltrane’s birth, secret tapes are emerging. What can they tell us about jazz’s great rulebreaker?

The sax star turned his back on fame to embrace free jazz. Caught on a tape machine hidden in an overcoat, newly revealed recordings show how he did it In August 1965, at the height of his fame, saxophonist John Coltrane headlined the DownBeat jazz festival in Chicago.

Taking to the stage with a new member of his band, young experimentalist Archie Shepp on tenor, Coltrane’s quartet blew through a series of jagged and free improvisations, straying from structured compositions and, instead, hurling down sheets of sound so loud and aggressive that they reportedly caused widespread walk-outs. DownBeat’s own reviewer later wrote : “They gave as tasteless a display of musicianship as I’ve ever heard … Shepp and Coltrane seemed to be more interested in trying to out-honk, out-squeal and out-bleat each other than in playing music. ” That 1965 performance should have been a triumphant moment, after five years of Coltrane’s star ascending. Since leaving Miles Davis’s “first great quintet”, with whom he had recorded what would become the bestselling jazz album of all time – 1959’s Kind of Blue – Coltrane founded an entirely…