It's something of a shock - as the curtain parts to reveal four men in suits, engrossed by their laptops – to discover that Kraftwerk are actually mortal. For around 30 years now, Kraftwerk's public persona has been one where vulgar human traits have been entirely sublimated to the steely image of the band. They are the robots. The man-machine. The showroom dummies. Even the fragments we know about their personal lives – that Ralf Hütter and Florian Schneider love cycling, chiefly – fit the profile of men symbiotically connected to their equipment.
As a result, part of what makes this rare show so compelling are the flickers of personality. The vast screen may be bombarding us with images of cyclists and trains, vitamins and calculators. But our attention is fixed on these four middle-aged Germans – Hütter on the left, Schneider on the right, junior members Fritz Hilpert and Henning Schmitz in the middle - trying so scrupulously to be dispassionate.
It is Hütter who first breaks cover, raising his hand to his mouth with a rather camp flourish whenever he sings. During the stainless techno of "Tour De France 2003" he begins, after a fashion, to dance, bending his knees fractionally, even bobbing his head. Schneider, meanwhile, is virtually catatonic, rarely even touching his mouse, though he looks more anxious than imperious. After a beautiful version of the original "Tour De France", he adjusts his microphone headset and takes a sip from a white cup. It is an epochal moment.
Kraftwerk live, in this relatively intimate setting, is a multi-faceted pleasure. The music, of course, is magnificent: crisp, simple, magisterial. There are moments tonight, particularly during a sequence that includes "Neon Lights", "Trans-Europe Express", "Metal On Metal" and an extraordinarily ominous techno update of "Radioactivity", when you feel that all other electronic musicians might as well pack up their laptops and go home. Even the tunes from last year's "Tour De France Soundtracks" don't sound incongruous in such elevated company.
But it's the tension between monumental, apparently effortless machine music and the betrayal of human quirks – like humour, say - that is most fascinating. Some of the jokes are predictably arch and design-led: tiny pulsing red LED lights on their black ties for one encore; glowing Tron suits for another; the band replaced by their relatively hyperactive android doppelgangers for a third ("The Robots", of course). Others are unnervingly daft. So as they march back on to play "Numbers", Schneider breaks rank and feigns a theatrical limp, before scuttling after his bandmates onto the podium.
After so many years cloistered in the studio, it's as if Kraftwerk are finally less frightened of showing their humanity: displaying themselves on their first proper tour for well over a decade; elegantly updating their fabulous music for a post-techno audience; even granting journalists the odd interview. They end with "Musique Non Stop" – which could, of course, have lasted all night. One by one, they play what amounts to a microscopic solo on their laptops, bow and walk off, stripping down the sound until only Ralf Hütter remains, smiling benignly.
"Goodnight, see you all next time," he says, and leaves. Naturally, the music continues, until well after the curtains have closed and the house lights have been switched on. The man-machine hasn't been dismantled, exactly. But inside this titanium-plated pop institution, amidst all the infallible circuitry, it's possible to see that eccentric human hearts are alive and beating.
