By the time the mercurial, volatile singer-songwriter John Martyn heard that he had been awarded an OBE for his contribution to British music, he was in a wheelchair, having lost a leg to septicaemia compounded by a lifetime of substance abuse. He died weeks later, before he could accept the honour.

Musicians often embody a garble of contradictions, but the English-born “Scots Belgian Jew” known to his family as Iain McGeachy was a more troubled – and troubling – figure than many from the late-60s. A trailblazing guitarist, he began his artistic life in the crucible of the folk revival that also produced Fairport Convention and Nick Drake. Solid Air, one of Martyn’s most magnificent outings, was written about Drake.

But Martyn took many of his extemporising cues from jazz and he went on to embrace nascent electronics, most particularly the early, spacious effect known as echoplex. U2 guitarist the Edge may not formally concur, but Martyn fans know the Irishman’s signature guitar sound was cribbed from Martyn. John Lydon and Bob Marley were admirers, as were Portishead. (In later life, Martyn did a sterling cover of Portishead’s Glory Box.)

By the end, Martyn had been impaled on a fence post and run into a cow with his car; artistically, he was yesterday’s man, having spent the 80s making slicker, more suffocatingly produced commercial rock music, often in the company of Phil Collins. There were periods when this leading light of the maverick fringe went dark, presumably to avoid the disreputable characters with whom he surrounded himself. The searching artistry of this caustic musician’s musician went hand in glove with dissolution and damage.

To his credit, journalist and biographer Graeme Thomson, author of previous well-regarded works on Kate Bush, George Harrison and Phil Lynott, dives straight into the awfulness of the man in the preface. “He blackened the eyes and broke the spirit of women he professed to love, abandoned at least one of his children and neglected others.”

Martyn’s parents separated when he was young, with his mother remarrying; the young Martyn felt the enforced distance from his mother, Betty, keenly. “He mistrusted women, which turned him into a misogynist,” states the folk singer Beverley Martyn, who suffered his violent alcoholic rages. Her own career did not survive their two-disc partnership; she eventually essayed albums of her own again much later in life, most recently in 2014. When the marriage broke up, Martyn left her, their two biological children and Beverley’s eldest child penniless; they lived off benefits while Martyn fuelled a coke habit. He started another family, forsook them too.

Somehow, this man had the gall to sing about love. Perhaps his best-known early song, May You Never, is an open-hearted blessing: “may you never lay your head down without a hand to hold”.

The remainder of the song’s lyrics touch on telling concerns, though. “May you never lose your temper if you get in a bar room fight,” Martyn husks. He saw many himself. According to his long-time musical wingman and carousing pal, the celebrated bassist Danny Thompson, Martyn once butted two men of a party of 12 after one racially abused a waiter in an Indian restaurant; the rest backed down. Tellingly, the well-wishing of May You Never reads, for the bulk of the song, like a dose of toxic masculinity garbed in lambswool; the verses double as a litany of paranoid fears of being badmouthed or backstabbed.

And yet Martyn, the difficult musical visionary, thoroughly deserves this painstaking and eloquent biography. It is not the first, but balances the fan’s assiduousness with a critic’s sieving action. Thomson does the legwork: the leading lights of the folk-rock scene, Martyn’s teenage girlfriend, Chris Blackwell, founder of Island Records, an early and loyal benefactor, Martyn’s children, umpteen band members, session musicians, producers and former managers are interviewed. One anonymous friend of Martyn’s is still too scared to go on the record about the musician’s underworld connections.

It would no doubt incense the scathing, unclubbable Martyn to learn how many of his peers-cum-rivals (Richard Thompson, for one) come to pass judgment on his abilities and frailties. What emerges is a picture of a one-man band musician whose virtuoso playing and jigsaw of effects units could, legend has it, upstage superstars; a charming boor with quicksilver in his fingers.

• Small Hours: The Long Night of John Martyn by Graeme Thomson is published by Omnibus (£20). To order a copy go to guardianbookshop.com. Free UK p&p over £15

Source: Small Hours: The Long Night of John Martyn by Graeme Thomson – review