As soon as Klara Soderberg produced some Irn-Bru to drink onstage, she and her sister Johanna could have called it a night and still received a fond reaction.

For all that the duo's success has come from projecting a lyrical style of world-weary folk, this was a performance that bounced with playful energy.

The guitar-playing Klara switched to drinking water later on, but there was fizz to the youthful twosome's manner. The sisters plugged the deluxe edition of their second album The Lion's Roar with sarcastic infomercialesque banter, dedicated numbers to Richard Dawkins and Pussy Riot and, at noisier moments, embarked on headbanging with some ferocity.

It's somewhat different from their actual music, often focused heavily around harmonies. They were impressive, with both vocals sounding crisp and soaring when required. Success this year has been rapid for the Swedish siblings, here supplemented by a drummer, but they adapted well to larger surroundings, with the snappy country pop of In The Morning and Blue a fine start. There was enjoyment in both quiet and loud moments, with the breezy Emmylou prompting a sing-along and a defiant I Met Up With The King dovetailing classic Americana with surprising aggression.

Covers of Fever Ray's When I Grow Up and America by Simon and Garfunkel were perfunctory, and a few songs ticked boxes efficiently without ever offering melodic inspiration. But the duo are still young, and when they beautifully performed Ghost Town with no microphones it was easy to believe they will someday match their obvious inspirations.

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