Russell Haswell was a shoe-in for the Autechre opening slot. Hunched over a rig seemingly plonked down at the front of the stage, arse in the air, Haswell brings screeching noise and deconstructed techno, lacerating ears and probably doing his back in (“do you need a chair?” someone unhelpfully chimes in). His extreme computer music finds a willing audience tonight (it doesn’t always), even the penultimate song which can be charitably described as a robotic pterodactyl being possessed by demons. Needless to say: a good start.

Mark Broom comes straight off the back of Haswell, providing the most accessible and danceable tunes of the night, playing a reasonably straightforward DJ set that moves from a hardgroove foundation to bring a bit of everything to the table. There’s choice samples of Roc Marciano (‘Broadway Billy’) and Ka over moody funk, dubbed-out reggae textures and some drum ‘n’ bass workouts. The light show hits a frenetic peak towards the end of the set as the seizure-inducing reds bounce faster than the speed of jungle. We get a fifteen break to prepare for the main act.

Autechre famously play in complete darkness, and the warning signs are illuminated before the duo take the stage. No filming, no phone use, no moving at all if you can help it. Expectations are expectedly high for their first Scottish show in over a decade, but there’s little time to get acquainted as the lights dip and a wall of noise roars into view.

“You had to be there” – surely the most pointless sentence in a concert review, but, well… With little discernible transition from song to song, the vast majority apparently unreleased, we’re rudderless in uncharted waters. It’s hard to describe the feeling that such an intense cacophony has on a 1000+ people standing in the dark. The opening sections are some of the most abstract, taking unpredictable and complex turns through refracted jungle and acid house. No beat is allowed to settle and it’s all being played at stomach-churning volumes. It’s awesome (in the classical sense, not the skateboarder sense) in the first instance, before your body and mind adjust and start to try and follow the patterns emerging. But the sooner you give up, the better. Just let it wash over you.

Time has ceased to be relevant, but maybe halfway through the storm reaches a crescendo and a recognisable 4/4 beat arrives and the disparate pieces begin to coalesce into a transcendent groove. Was it always there, is it there at all? It’s hard to parse and remember with all other stimuli cut off, like the concert is taking place in your own head for you alone; your own thoughts, expectations and biases all adding to the experience. An unexpected inversion of John Cage’s 4’33 that somehow activates the same receptors.

All of the above drivel notwithstanding, this isn’t 100% the pure auditory experience that Autechre wish it could be. Thanks to what I assume is health and safety regulations, the room isn’t completely dark. Small lights can be seen here and there, and even onstage there are occasional flashes from the duo onstage, like fireworks seen on the horizon. People come and go, there’s the odd flouting of the ‘no phone’ rule, so you can’t maintain your focus absolutely unchallenged. But it’s the best you’re ever likely to get. The sound is fantastic; crisp and punishing, the percussion hitting like giant pistons, the bass reverberating in a satisfying thump. The mood is quietly jubilant, switching from the initial awe, through wonder and joy, to an eventual burst of emotional catharsis at the grand finale. Worlds were built and then thoroughly obliterated by the end of this 90 minute onslaught.

This is electronic music of the highest order, moving far beyond any restrictions of genre, volume or trend. Rob Brown and Sean Booth have developed their cult-like following for over 30 years now and it’s easy to see why after experiencing it. You simply had to be there.