Southern Tenant Folk Union, King and Queen

“If you’ve got the heart,” sang a suave Ewan Macintyre, “then you can be involved, you can be a part”. There was more heart in the room last night than you’d find in a whole tour of Mumford & Sons. And art. Nothing too flashy to begin, just lovely interwoven mandolins and fiddles, driven by guitar rhythms and their trademark bluegrass banjo. Southern Tenant Folk Union might have been playing in a boozer, but if people call these guys a jumped-up pub band, they've got it all wrong.

Southern Tenant Folk Union was formed in 2006 in Edinburgh, by Pat McGarvey, who played a five-string banjo that brought a slice of the Appalachians with it. Their fusion of Celtic, British and American roots music gave them a sound that, while quoting everyone in sight, was still original. The last album, the conceptual The New Farming Scene, earned enthusiastic comments from those critics who received one of McGarvey’s hand-typed PR packs. And last night they were hoping their new one, Pencaitland, might get a similar reception.

Played in its entirety over the first half, it was tasty stuff alright. A little less immediate than the predecessor, a few songs in it started to confirm itself as equally rewarding. Again loosely conceptual, this time we were told we were in a post-apocalyptic dystopia. Or at least it amused the seven-piece band to find ever more inventive ways to introduce the songs thus. Vocal duties were roughly split between the dashing Ewan Macintyre and the cheery, pot-noodle-haired Jed Milroy, with McGarvey keeping a slightly anxious eye on things from the side.

Huddled around one microphone in a room thick with humidity and expectation, the evening got off to an auspicious start with one of McGarvey’s spectral sci-fi folk numbers, “I Dream of Burning Buildings”. A puppeteer by day, Macintyre’s voice over the evening went from balladeer to crooner to Elvis impersonator and back. Milroy opened up his vocal account with the renewal song, “At the Break of Dawn”. Less versatile than Macintyre, he was, in his own way, equally effective through the way he inhabited the songs.

Compared with former offerings, McGarvey’s bluegrass influence was less apparent on this new album. Still, the most overtly banjo-orientated of the songs, “Ida Won’t Go”, was also one of the highlights. Writing duties on the record have been mainly split between McGarvey and Milroy, but most of the other members contributed a song. Former embalmer and fiddle player Carrie Thomas set a friend’s poem called “The Tide” to music, Macintyre sang of the hard graft he’d sometimes have to resort to in “Labour Season”, but it was Chris Purcell’s Dylanesque “It Takes Time” that had people’s jaws dropping.

The second set was the fun set. The first half had been a journey of the imagination, but it offered little by way of showmanship. After 10 o’clock they let rip. The bluegrass and smiles broke out. Middle-eights became jam sessions, Jenny Hill’s fingers improbably bounced around the double bass fretboard that dwarfed her, and Adam Bulley’s mandolin started smoking from his folk-star solo heroics. But it wasn’t just light. The high spots came when they moved away from sounding like they were in the back of an Alabama speakeasy, and played the big numbers from The New Farming Scene. “Let Me Wipe the Tears from Your Eyes” was as lachrymose as the name suggests, “TA9” was simply beautiful, and “Hardy” almost shook the windows from their sashes. It was like listening to Fairport Convention after they’d all had a few.

For the encore, the band turned the mic off to perform an Alaskan wedding song, “Old Black Crow”. But really they’d been playing virtually unplugged all night. It would be a real treat to see what they could do with full amplification and a proper stage. But even then the STFU might just prove a little too rustic to ride the current Mumford & Sons folk wave. They just aren’t as fashionably beardy. They wear suits, not ersatz Americana check shirts and braces. And they don’t seem to have quite enough self-belief. But although their name comes from another country and era, what Pat McGarvey’s boys and girls do is keep folk music alive, contemporary and real. And for the second time this year, a Scottish folk collective have shown how excellently that can be done.

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Watch Southern Tenant Folk Union playing the Isle of Man