Mumford & Sons, Scala, London

With their first album out on 5 October, Mumford & Sons' London performance was a key test for the young English folk group who've already been tipped for next year's Mercury Prize. With a sold-out venue and anticipation about the show high on the back of much recent hype, there is nonetheless something dark and confessional in songs like "White Blank Page", which resonates with an audience who observe the tribute to lost loves unfold with a reverence rarely witnessed at live performances. Even amongst the broken tiles and sticky floor of a venue far past its best, Marcus Mumford's vocals seem to soar.

What is most captivating about the performance is the ensemble's ability to straddle different genres and simultaneously to innovate within them; the vocal harmonies reach the heights achieved by their folk contemporaries Fleet Foxes, particularly on the album's title track, "Sigh No More". Mumford's vocals alone are charged with all the emotional intensity and rugged charm of Bon Iver, while much of the evening's instrumentation recalls the American indie group Beirut. As far as these influences go, they are pointedly modern references within a genre typically characterised by an uncomfortably old-fashioned and English way of life.

Never has a one-man band seemed so artistically valid as those moments in the show when Marcus Mumford accompanies his singing and guitar playing with a bass drum which he kicks with one foot to give the performance a percussive edge, as on "Roll Away Your Stone". The whole set is remarkably pacey, with few breaks for audience interaction in the first half.

Later, when Marcus Mumford does take the opportunity to talk to the audience, it is to thank them for the unbroken attention they've lavished upon the the band's five permanent members and other assorted musicians who've accompanied them over the course of the evening.

The evening concludes, not with the fan favourite "Little Lion Man", which is dispensed with earlier, but with the previously unheard "Whispers In The Dark". As a tide of awestruck fans pours out into the street, I overhear one gruff observer pose the question that many must have been asking themselves over the evening. "So is folk now cool with the kids?" he asks; and, with such a pronounced mood of jubilation amongst the crowd, the answer seems obvious.