Mumford & Sons, Delta, review: dark and thrilling, this is their best album yet

Mumford & Sons: Ben Lovett, Marcus Mumford, Winston Marshall and Ted Dwane - AP
Mumford & Sons: Ben Lovett, Marcus Mumford, Winston Marshall and Ted Dwane - AP

Visiting producer Paul Epworth at Church Studios this year, I was struck by the variety of instruments scattered around: alongside double bass, grand piano, acoustic and electric guitars, there were mandolins, accordions, all kinds of exotic folk and percussive instruments and a formidable array of banjos. "Have you got Mumford & Sons in here, by any chance?" I asked.

The Mumfords may be the most unlikely success story of the modern pop era, an old-fashioned quartet of folk rockers who stand like luddites in the path of the all-consuming electronic dance behemoth. Their first three albums all topped the transatlantic charts. For their fourth album, Delta, they have brought in Epworth, the producer behind Adele.

You can just about detect a new patina of synths and vocoder effects, although when the band is at full tilt, you could probably hide a kitchen sink in the blizzard of sound. This lusty rambunctiousness is balanced by passages of gentle intimacy, with everything dropping out to leave shadings of percussion and chords under Marcus Mumford's world-weary vocals.

"What if I need you in my darkest hour?" he asks on the opening track, 42. Given the band's background in the Vineyard church, he presumably refers to Psalm 42, which pleads for God to show himself in a time of political trouble. A struggle between light and darkness permeates Delta, and soon a particular characterisation of darkness takes hold.

Picture You grapples with the onset of depression, culminating in a storming coda called Darkness Visible, after the American author William Styron's 1990 memoir about his mental health. The phrase is itself borrowed from Milton's Paradise Lost, excerpts of which are recited while the Mumfords unleash their angst on the entire contents of the studio. It is a furious, overloaded, utterly thrilling piece. Mumford & Sons have steadfastly declined to identify themselves as a Christian band, preferring to assert their faith in the transformative power of music. Delta is their best album yet, spiritual solace wrapped in secular anthems.

Delta is released by Island on November 16