Marcus Mumford is likely to be found starving, bleeding, dying, sighing, fading, sinning, hopeless, "in the dark" or – as the new song Broken Crown puts it – "crawling on my belly under the sun". Lyrically, not much has changed between Mumford and Sons' debut album and the new one, Babel, premiered tonight at the iTunes festival. But the shiny, statuesque, A-list celebrity on stage appears to be a spokesperson for generalised human woe, and the crowd bond immediately, stomping, folk-dancing and commiserating their way through Little Lion Man together.
The band are tough on them tonight, though: they prove reluctant to "do the old", and play three new songs in the first 20 minutes (starting with the downbeat Lovers' Eyes). It becomes obvious how much their show depends on that signature ram-raiding attack on guitars and tom-toms – one dramatic "thrum" from Winston Marshall and the crowd screams as if he's taken his shirt off, but lose that backing and people start having a chat. The music Mumford play is not melodically complex; that's partly why they're free to jump around so much. But two songs stand out tonight for subtlety: Thistle and Weeds, all mariachi horns, cymbals and dislocated groaning ("rain down!"); and the intriguing Dust Bowl Dance, with its naked banjo part. There's also a super-quaint moment when they gather up the front for an a cappella version of Timshel in four-part harmony.
"So long since we've had a chat and a catch-up," says Mumford. It's their homecoming gig, of course, after an ecstatic US tour. Funny the way they've managed to sell back to America the music America does best. Maybe their Irish and Scottish-tinged tunes sound like music "from the source". As The Cave rings out, it's clear their particular brand of blockbuster bluegrass has life in it yet.
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