Browsing through various past reviews of The xx, two adjectives which occur time and again are “fragile” and “tentative”. These are wrong – but understandable.

It comes to something when the logic of a German act calling themselves “Gas” is the least troubling element of a perfomance. Not that Wolfgang Voigt's ambient music, or the slowly-evolving digital art of Petra Hollenbach projected on the Barbican's cinema screen, contained any obvious shock tactics – but the whole 80 minutes created just about as unsettling an experience as one could imagine from abstracted sound and image.

Orbital occupy a singular position in the pantheon of Nineties dance live acts that made it to arena-show status. Paul and Phil Hartnoll's trademark shaved heads and specs-with-headlights gave them a massively spoddy image that belied an everyman quality to their music, but although their early releases unquestionably helped form the distinctively British sounds of rave and hardcore, they never quite became part of those scenes.