If a hefty percentage of Americans think Mumford & Sons grew up chewing cornstalks in Downhome, Alabama, it's largely the fault of US nu-roots sensations The Avett Brothers for playing Maggie's Farm with them and Bob Dylan at the 2011 Grammys. Since Appalachian bluegrass is actually part of the culture of these North Carolina siblings, they're far more playful with it, giving a fresh skip to Americana's dust-road step.

The core duo of Scott and Seth Avett on banjo and acoustic guitar is flanked by a double-bassist and a black-Stetsoned, moustached cello player roaming around like an evil gunslinger auditioning for the 1978-vintage ELO. Together they summon a stomping vaudevillian bluegrass with offshoots of chamber music, powerpop, calypso, Celtic soul noir and even some on-trend Fleetwood Mac cool. When they do succumb to the trad barndance, on Laundry Room, they do it with punk bite and throw in a double-bass trip-hop solo. All this while spinning backwoods philosophies about being "a coin, pulled from an empty pocket, dropped into a slot with dreams of sevens" and bouncing through At the Beach with jubilant, rubber-boned submersion.

For all the suppressed mania in Scott's trembling lyrics of madness and malcontent and his general air of a tub-thumping snake oil salesman, their first hour is an insanely sunny whirl. But a spot-lit segment where Scott and Seth harmonise crushing paeans to lost parents (Through My Prayers, from 2012's US No 4 album The Carpenter) and their attempts to stop being alcoholic idiots (When I Drink) adds tangible depth that lifts them above the hoedown hoi polloi. Defiant ballad I and Love and You and a closing bunch of rousing reels ensure no partner leaves unswung. The 'Av It Brothers, more like.

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