Until recently, the self-titled 1967 album by Danish pianist Tom Prehn’s free-jazz quartet was the group’s only available document. Then, in 2015, their aborted 1963 recording, Axiom, was given its first full release, revealing an extraordinarily sophisticated and radical aesthetic – and a contender for the first European free-jazz album ever recorded. The story goes that Prehn asked for Axiom not to be released because, by the time it was ready to press, the group had already moved on. The two 40-ish minute suites contained on this new archival find indicate where they’d got to.

‘Centrifuga,’ recorded in August 1964, is a dense smoulder hung on Finn Slumstrup’s kinetic drumming, with the others taking turns soloing with youthful zest and Prehn’s torrential piano suggesting he’d witnessed Cecil Taylor’s famous 1962 shows in Copenhagen. ‘Solhverv,’ recorded in January 1965, is slightly shorter but no less intense, with tenor-player Fritz Kogh burning in the fierce momentum generated by Slumstrup’s brush-work and unleashing cool abstractions. An astonishing section where he investigates percussive effects generated by closely-miked key pads could have been recorded any time in the last year.

Previously only existing on private reel-to-reel tapes, these preternaturally advanced sounds must be heard to be believed.