There is plenty of evidence of traditional music’s buoyant vitality in a sparkling set from the four-piece Keep It Up, who bring a marvellously expansive spontaneity - as well as tremendous technical flair - to their repertoire of traditional and traditional-style tunes. The vibrant, luminous pairing of Simon Thoumire’s mercurial concertina and Eilidh Shaw’s perpetually restless fiddle seemed to be goading each other on to ever greater heights of semi-improvised invention, while guitarist Kevin Mackenzie and Malcolm Stitt on bouzouki cleanly but forcefully underscored their playing’s muscular lift and swing