We heard the news of the collaboration between James Blake and Bon Iver with interest and trepidation. After all, Bon Iver had been a pioneer of a rootsy prototype of the Blubstep form adopted by James Blake on his album For Emma, Forever Ago: both men are capably of producing introspective slightly mopy records recorded in shed or bedroom. But after Bon Iver's far more upbeat and inventive second album, what of this pairing up? After all, we're huge fans of both James Blake's non-LP work and Bon Iver. Had the Blubstep Jims (Messrs Blake, Woon and XX) concocted a plan to kidnap Justin Vernon and bring him back to the sensitive side? Or had the reverse happened, and Bon Iver sat James Blake down with the dudes from Gayngs, a massive bong, and the best indie grumble he could find? Did Vernon then say "Son, like you I would sit at my music making machines, shedding small tears for a woman who no longer loved me. But then I saw the light, and realised that with a whack of Autotune and a sound smoother than Belgium's Charles Ubaghs, everything would be OK"? You can listen and decide for yourselves below. We're not sure about the upset farm animal sound effects.