At the far end of the Primavera site there’s a massive concreted car park the size of four football pitches that houses the festival’s two huge main stages, lined up alongside each other like some ruthless legion of big-name festival headliner efficiency. The area, all unforgiving scorched earth and brutal engineering, has acquired in recent years the nickname “Mordor” to reflect its, ahem, fairly demanding environment and distance from the festival entrance.

But if Primavera has a Mordor, it also has a Shire, in the form of the Auditori Rockdelux at the top of the site – a beautiful, comfortable, and acoustically pristine concert hall reserved for three acts each night whose shows, for whatever reason, wouldn’t really work as well on one of the festival’s outdoor stages, and it’s here that Autechre make their first live appearance since 2018 in what could well be one of the most inspired bits of programming of the whole weekend: one might not necessarily expect the duo’s brand of fractured acid techno to be the perfect fit for an early-evening day-two opener, but it turns out that it’s the perfect set-up for the subsequent evening’s entertainment, a sort of total aural reset designed to tune ears for the more regular fare to come.

The duo perform, as ever, in the pitch black, and make full use of the Auditori’s spatially and sonically huge PA to generate a quasi-hallucinatory experience in which sound starts to acquire physical heft and shape. It is just about possible to parse in real time the music being performed, following pulse and timbres as they veer in and out of deconstructed abstraction, but it’s far more satisfying just to allow a sort of sensory jet-washing, staring into the darkness as the electronic and synthetic becomes utterly organic and takes on a flawless but undefinable internal logic of its own. With this latter approach, Autechre’s music becomes not just complex and abstractly beautiful, like a Jackson Pollock canvas in sound, but also completely rejuvenating, like a granite scrub for the aural pathways, much needed in the middle of a weekend with so much sonic detritus in the air.

An hour later (although it feels, simultaneously, like both five minutes and a week), the clatter subsides into a calm drone, and our group session of dual sensory deprivation and overload is done. As the lights come back on, it’s just possible to see the duo stuffing their laptops into their backpacks and scuttling off backstage like a pair of hotdesking employees with an appointment elsewhere. The rest of us, rubbing our eyes and shaking our heads to rinse off the residue of what’s just happened, file out into the rest of Primavera’s Middle Earth, infinitely more ready to attack the night than we were 60 minutes previously.