Support act Explosions In The Sky understood that the right two notes, plaintively repeated, can be all you need. They dealt in the slow, slow build, hoping eventually to overwhelm you with great swathes of guitar, and it worked often enough.

Headliner Kieran Hebden is often blessed with a quiet genius, as both his Four Tet solo venture and Fridge project have demonstrated since the late Nineties.

He has recently forsaken the pastoral delicacy of old for a fresh, abrasive strain of electronica.

Beauty has always seemed to come easily to him and he should be applauded for continuing to test himself. The problem here was that much of his set felt like an endurance test for his audience, a steady trickle of whom fled the hall.

There were great moments, admittedly, when Hebden sounded like he had an entire gamelan orchestra jamming in a malfunctioning amusement arcade and others when he returned to the simple pleasures of old.

But too often he strayed on to the wrong side of the fine line between patient, adventurous construction and fruitless indulgence.

The question of what lies beyond orthodox melody and rhythm is one which needs to be asked. But the answer ought not be that the audience spends much of the time wondering if they switched the lights off before they came out.