Journalists who coin comedy names to pigeonhole music are, as any band will tell you, the worst kind of scum. But it's hard not to feel a spasm of admiration for the writer who first described Ambulance LTD as "nu-gaze", in honour of shoegazing, the early 1990s movement that foregrounded intense soundscapes and considered audience interaction a feckless indulgence.

These four lanky New Yorkers start as if they mean to revive the genre. Yoga Means Union begins with a few gently picked guitar notes, before moving via some punchy drumming into a charged, cyclical jam. It's atmospheric, absorbing, and very, very serious.

If this were Ambulance LTD's only setting, the band would not be as feted as they are: the quartet are supporting REM on their forthcoming mega-tour and have managed to unite Lou Reed, the Bravery and the Killers in praise. Their impressive debut came out last year in the US, although it is only just getting its full UK release.

As well as droning epics, Ambulance LTD are big fans of the summery pop song. Forthcoming single Primitive (The Way I Treat You) is jaunty and callous, while Anecdote burbles along sweetly. When a new song drifts off, taking the audience with it, a splendid blues pastiche rushes in to save the day.

The group could do with more presence. Singer Marcus Congleton fiddles with his guitar and effects every time he is called upon to speak. Without a focal point, you notice the edges of the performance - the way Benji Lysaght's nostrils flare when he plays his Hawaiian guitar, and the way the crowd holler for an encore out of politeness rather than passion.

Congleton returns, with a neatly ironic order to "settle down" but the closing numbers serve to underline that Ambulance LTD are a promising new band, not the finished article.

· At the ICA, London SW1 tonight. Box office: 020-7930 3647.