Today’s avant-garde is tomorrow’s mainstream?as was the case with Monk. When widespread success finally arrived, there was this nagging suspicion he didn’t quite know how to deal with it. Columbia made much of his ‘eccentricities’?the hats, etc?and the truly bizarre cover of Underground (1968) aimed him squarely at acid-rock fans into ‘weird’.

The acclaim may have been more, but it didn’t herald a creative quantum leap. No abundance of fresh material or any noticeable new direction. Monk just carried on as before repeatedly picking over the innovative repertoire he’d previously created on Blue Note, Prestige and Riverside?always the first place to begin.

But Monk wasn’t the first to strip down and reconstruct his past work. Neither did he overly concern himself with recording technicalities. Often, the listener gets the feeling of eavesdropping on him working out ideas, mainly with his quartet. But for those prepared to forage, there can be moments of genuine revelation.