Jason Isbell and the 400 Unit, The Garage, London

Jason Isbell strides onstage and apologises for the slimmed-down nature of his band, trimmed from five to three for his current tour. "We're not so much the 400 Unit tonight as the Jason Isbell power trio," he admits, but nobody's complaining: Alabama blue-eyed soulster Isbell has the burly, no-nonsense look of someone who can take care of himself pretty well. Besides which, he's one of the few guitarists for whom the phrase "power trio" doesn't portend endless indulgence, but rather an attention to texture and rhythm that plugs any holes in the arrangements.

The trio slip with the practised smoothness of a road-hardened band into the country-funk swing of the Candi Staton classic "Heart on a String", Isbell's licks effortlessly blending rhythm and lead parts behind his smoky, coffee-toned vocal. Then it's "Alabama Pines", the opening track from his excellent new album, Here We Rest, its gentle yearning undiminished by the change from acoustic to electric setting. Later on, he'll close the set with solo versions of Todd Snider's "Play a Train Song" and his own Steve Earle-esque sharecropper ballad "Thank God for the TVA" which suggest that should he ever lose the 400 Unit, Isbell would excel as a lone troubadour.

But it's to his credit that Isbell's love for the multi-racial soul heritage of his native Muscle Shoals means that's never going to be an issue: this is music which demands the sinuous interplay of a band well schooled in the intricacies of country, Southern soul and funk, the latter capabilities demonstrated when the trio end with an impromptu encore of The Meters' "Hey Pocky Way" which somehow manages to incorporate every last bump and roll of the second-line rhythm in its skeletal groove.

In between, the set mixes standout singalongs from the new album, such as "Go It Alone" and "Codeine", with heavier blues-rock cuts from his time with the Drive-By Truckers, notably a "Never Gonna Change" which transforms into a sterling cover of Hendrix's "Stone Free", unfortunately cut short by a malfunctioning amplifier. Elsewhere, the railroad shuffle "Tour of Duty" shows that Isbell is equally at home emulating country-rock pickers like Clarence White, while a quicksilver slide break illuminates "Danko/Manuel", which offers the most heartfelt affirmation of the tradition he's keeping alive.