"I just don't get it. Maybe I'm not supposed to." Kurt Wagner, leader of Nashville's alt-country/soul wonders Lambchop, sits stunned by the audience's ecstatic reaction. Bizarrely, he doesn't think he's any good. This is despite writing and singing the songs for a 20-piece band who are reinventing American music right before our eyes.

Wagner and co's performance unveils a new twist on the old "quiet storm", a term invented by black American radio in the 70s to describe all those seduction songs by the likes of Al Green, Isaac Hayes and Luther Vandross that revel in a restrained eroticism. Despite coming from a supposed indie-country background, and looking like the PTA committee at some hicktown school, Lambchop use strings, horns and ageing keyboards to produce a graceful soul sound that whispers sweet nothings into your ear. Moving from gruff whisper to girlish falsetto, Wagner offers an extraordinary brand of conversational poetry - squabbling neighbours, apologies to long-suffering lovers - that celebrates the supposedly dull and downtrodden masses with a wry and profane wit.

Pulled from this year's Nixon album, the live versions of The Old Gold Shoe and Up With People make recorded songs sound like demos. The crowning glories are versions of Curtis Mayfield's Give Me Your Love and Teddy Pendergrass's Love TKO, soul classics that your average white band would either castrate or camp up. But Lambchop are special, a labour of love hewn from a music lover's modesty. Kurt is right - if he got it, his ego would get in the way of this inspirational magnificence.