Those of you deeply into both jazz violin and progressive rock no doubt jumped right on the play button above. Quite a few more will listen — so experience has taught me — purely out of interest in anything and everything Pink Floyd has done. But on the level of music history, the track above, a version of the cerebral English rock band’s Pink Floyd’s well-known 1975 song “With You Were Here” prominently featuring a solo from the French “Grandfather of Jazz Violinists” Stéphane Grappelli, should fascinate just about anyone. It speaks to the particular kind of high-profile musical experimentalism that thrived in that era, at least in some quarters — or, rather, in some studios. In this case, the Grappelli and the Floyd boys found themselves recording in adjacent ones. Why would the latter invite the former, already an elder statesman of jazz and a collaborator with the likes of Django Reinhardt, to sit in on a session? (Watch Django and Grappelli play together in the 1938 film, Jazz Hot here.) Well… why not? They needed something impressive to follow Dark Side of the Moon, after all.

Still, for all the richness of the result you hear here and all the fan-hours spent listening to Pink Floyd’s Wish You Were Here album in the 35 years after it came out, the public never got to hear Grappelli’s playing foregrounded until Immersion reissued it three years ago. This long-lost but rediscovered mix of the title track marks, to the mind of Pink Floyd founding member Nick Mason, a marked improvement over the version on the original album. “I think that was the jewel in that particular crown,” he said to Sonic Reality. “It was something that I assumed had been lost forever. I thought we’d recorded over it. [ … ] I can’t imagine why we didn’t use it at the time.” In the one they did use at the time, what remains of Grappelli’s playing came out so inaudible that the album’s credits didn’t even name the violinist. I’d like to chalk up another point for the cultural revision made possible by our technological age, but alas, I doubt any sort of rediscovery will break true Floyd acolytes of their adherence to the canon.