Grizzly Bear, Koko, London

So, Grizzly Bear are a pretty cool band to name-drop in 2009, and with good reason. Their stunning third album, Veckatimest, is already being touted as one of the albums of the year and they have received public gushing endorsements from a number of acts, including Fleet Foxes and Radiohead. And yet they seem more surprised than anyone that their complex brand of experimental folk-pop is such a winner, and that they're now playing venues the size of KOKO.

With meek waves, four slightly dorky-looking guys arrive and take their places behind the instruments which are arranged evenly across the front of the stage: in concert, each member of the band is the frontman. They go straight into Veckatimest's opener, "Southern Point", for which the band's founder, Daniel Rossen, takes lead vocals. It is a soaring track which builds with layers of guitar, tambourine, drums and the added vocal harmonies of the other men. And this is what makes their music so striking: the myriad sounds that comprise each song; how the tracks often have phases and change direction; the slow build up to release.

"Two Weeks" blends Beach Boys-esque keyboard pop with lugubrious, haunting harmonies to lament a doomed relationship. "Foreground" is another exploding choral track that devastates the crowd. For "Knife" (from their second album, Yellow House), Ed Droste and Chris Taylor take up vocal duties and the result is a spine-tinglingly beautiful ode to Phil Spector's Sixties girl group sound, updated with folk elements. For their encore, the band even play an eerie version of the Crystals' "He Hit Me (It Felt Like a Kiss)".

There are a couple of minor quibbles. On occasion, a track will drag a little bit, and "Lullabye" sounds a bit messy. With too much going on, it loses the precision that their music requires.

The gig is a low key affair. Those who prefer more action in their shows – furious solos, witty banter, the opportunity to really let your hair down – may need to look elsewhere. Indeed, there's the odd restless shout out from a bored crowd member. But Grizzly Bear's is a modest, beautifully executed performance that evokes past summers and old loves. It's one that requires patience from the audience. This October they play with the LSO at the Barbican. If the opportunity arises to make it to this sold out show, grab it with both hands. They're a class act.