"That thin, wild mercury sound," is how Bob Dylan described the feel he was chasing on Blonde on Blonde.
But that didn't stop someone shouting "Judas" at him when he ditched his acoustic guitar in Manchester in 1966.
Coming out of London's fashionable Fulham Road area dressed like west country novelty act The Wurzels, Mumford & Sons had some strong songs.
They were smart. Marcus Mumford (left) had read classics at Edinburgh University. Their debut album Sigh No More took its title from a line by Shakespeare in Much Ado About Nothing. From Plato to Steinbeck, lyrics referenced literary greats. Their angst sounded rather jolly.
The band's sound was built around bluegrass and folk, with rarely heard banjo and accordion creating an alternative noise to... well... alternative noise. They were a welcome diversion from Justin Bieber and Susan Boyle.
Charming to a fault, they took their coals to Kentucky and found favour in America where their Range Rover gentleman farmer chic struck a chord with the good ol' boys.
The Mumfords were feted, gigged at the White House for Obama and Cameron and won awards as their second album, Babel, went to No 1.
Kings of the hobo jungle, Mumford and cronies set their sights on some new city on the hill. To get to this mythical place, these cats reckoned they needed to ditch the Dick Whittington nonsense and hitch a ride on some high-end luxury motor.
So, like Dylan before them, the Mumfords went electric for this new 12-track collection. They've decided to rock out. Uh-oh. The heckling you hear isn't "Judas". It's much worse than that.
It's an odd thing. The swelling choruses are still there. You can hear their trademark lift on Ditmas, where surging voices act as a foil for the plaintiff bleating of Marcus. "Don't tell me that I changed, because that's not the truth..."
They've switched producer. But what The National's Aaron Dessner was thinking getting involved with this turgid sonic broth is beyond me.
On the plus side, it may be that there are some decent songs languishing under the stale bombast that seems inspired by the sheds, those cavernous touring venues of the mid-west, where bands disappear into an eternal touring limbo providing in-the-moment epiphanies for the pimply, the obese and the psychotically deranged.
Ill-judged, over-blown and tedious, even Judas might find it hard to pardon Wilder Mind. HIIII