APPARENTLY, the Yeah Yeah Yeahs are “cool”. For the past year, magazines devoted to the fashionable have queued up to lavish praise on the Brooklyn trio, salivating at extravagant length over the ad-hoc style of their frontwoman, Karen O.

Such froth, coupled with the idiotic ravings of the New Musical Express, have created a tsunami of hype which no band — especially one that has released only two singles so far — should have to face down.

Happily, the Yeah Yeah Yeahs are apparently unfazed by all the attention. Slamming out a 17-song set at this packed and sweltering London venue, they showed that they are a dynamic musical force, not some glossy media construct.

Being a three-piece their sound is minimalist, but this only ensures that every bullet-headed note emanating from the wide stage is heard loud and true.

Bespectacled powerhouse Brian Chase’s supple, muscular drumming reminds you that rock’n’roll’s organic rhythms can be just as danceable as club culture’s programmed pulse.

He has the perfect foil in Nick Zinner on guitar: a thin, black-clad figure whose lean-riffing style joins the dots between punk economy, distorted blues and surf noir.

There’s no bass, but it’s not missed, the group channelling their serrated noise into phenomenally taut song structures. The gothic freight train beat of Machine, for example, crackles with a pre-coital tension — even before you heed Karen O’s panting, pent-up vocal.

Resembling a female Peter Pan in her ripped tights and red, white and green shorts, the singer is gloriously unselfconscious. She skips, writhes, bends over backwards and falls to the floor, all the while flicking her messy black hair.

Her voice is electrifying, whether she’s screaming into the void on Art Star or turning feline sexual predator for the clipped put-downs of Bang.

The latter’s reversal of rock’s traditional gender roles is both empowering and overdue. Half the audience want to be Karen O and half want to be with her, but the demarcation isn’t necessarily along male/female lines.

The woman herself is so wrapped up in her performance that she barely seems to notice, which just drives everyone wilder.

By the end, 2,000 people have become a steaming mass of sweat and smiles. Honestly, cool doesn’t enter into it.