I was just Googling the line-up of All Tomorrow’s Parties in 2001, curated by Mogwai (whose still-exhilarating debut album, in deluxe reissue format, was playing five minutes ago). Looking back, I must have been in hog heaven: Godspeed You Black Emperor, Stereolab, Super Furry Animals, Labradford, Ligament, Shellac, Papa M, The For Carnation, the great and good of post-rock and, notoriously, Sonic Youth.

I was just Googling the line-up of All Tomorrow’s Parties in 2001, curated by Mogwai (whose still-exhilarating debut album, in deluxe reissue format, was playing five minutes ago). Looking back, I must have been in hog heaven: Godspeed You Black Emperor, Stereolab, Super Furry Animals, Labradford, Ligament, Shellac, Papa M, The For Carnation, the great and good of post-rock and, notoriously, Sonic Youth.

Sonic Youth headlined on Saturday night, played an extensively improvised set, and managed to piss off quite a large proportion of their assembled fans (including, if memory serves, one or two members of Mogwai themselves, but don’t quote me on that). Heroically, the SYR series of releases is reactivated this month with “SYR7”, which turns out to be, on its A-side at least, 20-odd minutes of that free, elevated jam, now titled “J’Accuse Ted Hughes”.

When I tried blagging a copy of this record a week or so back, the publicist expressed surprise that I remembered the show so fondly. Surely, she suggested, I’d slagged off the performance in NME? I denied this, albeit slightly anxious that I might be getting things terribly wrong. But then she found the clipping, and the review was written by James Oldham, another big fan of the band, who now runs Loog Records and A&Rs Duffy, amongst others.

James described the gig as “something close to a living hell”. He writes about the first song, which may well have been “J’Accuse Ted Hughes”, like this: “At 10pm, Sonic Youth amble onstage and start playing what sounds like the run-out groove of ‘Bad Moon Rising’. After ten minutes of meandering two-note fluctuations, bassist Kim Gordon starts singing. Badly. Ten minutes later, the rhythm changes slightly and Gordon starts hitting a block of wood. Ten minutes after that, they’re still up there noodling away. . .”

From then on, he starts getting really disparaging. Weirdly, though, take out the negativity, and it’s a fairly accurate description of this glowering, ominous piece – far more accessible, incidentally, than some of the SYR releases which have preceded it. There’s a rippling, meditative quality which is possibly reminiscent of something from the middle of “The Diamond Sea”, and it strikes me that what people found so alienating about the set was the lack of context. If Sonic Youth had framed this trip with even a minute or two of more conventional melody, such a longueur would have been assimilable. Here, though, it has the unanchored fervour of free jazz.

Kim Gordon’s freestyle incantations, we can now hear, veer from “I will fuck you” to “I sent my poem to Good Housekeeping. They paid me ten dollars”. I have a new Free Kitten album, by the way, which I should get round to writing about in the next week or so.

Anyway, “J’Accuse Ted Hughes” is backed by a 2003 studio piece called “Agnès B Musique”, a really lovely, humming piece of deep space drift played on and mixed by Jim O’Rourke, which reminds me a bit of an organic version of his glitch record for Mego that came out around that time. Bit of something Krautish here, too; Faust, maybe, at their most casually industrial.

Whatever: it’s good, it’s probably a limited edition, and “SYR8” is due on July 29, featuring a 2005 performance at the Roskilde Festival where the band were augmented by Mats Gustafsson and Merzbow. Bring it on!