Lau, Manchester Dancehouse Theatre, 17th May 2015 9/10

At its best, live music can transport you to another place. Issues with the venue meant that one of my favourite live bands, Alabama Shakes, had failed to do this the evening before. Instead, it was the more nuanced stains of Celtic music that succeeded in soothing the strains of the world. Aided by a hushed venue, with photography strictly banned, I was entranced by the ethereal singing of Glaswegian support act Siobhan Wilson. She brings the influences of classical composition and time spent in France to her songs, but it was the emotional directness of her soprano vocals, self accompanied by acoustic guitar that I found so touching. Lau, by contrast, is all about the interplay of three musicians who've played together for years and can sense each other's feeling intuitively. They share a sensitivity with their compatriot Siobhan: a song like Ghosts, speaking of the memories of generations of migrants, creates such a delicate atmosphere.

For all their debt to traditional music, Lau is unafraid to look outward, not just in singing about immigration, but advocating threatened creatures in Save The Bees and displaying a banner on stage proclaiming ' I Love the NHS'. In an interview, Martin Green explained that they didn't make a decision to play a particular genre of music: “We all started playing as children, so there were no lightbulb moments of ‘my God I just have to take up the accordion'. I was playing the accordion before I knew any better.” Scottish folk may influence the instrumentation, but it's merely a starting point for their music, which goes on an imaginative journey. The thematic development of material, most notably in The Bell That Never Rang recalls classical music. Kris Drever's distinctive sounding vocals do not appear until ten minutes into the song, and instrumental passages are often at the emotional core. On the the new album of that title, the trio are joined by the Elysian String Quartet; alas they are not touring with Lau. The deep symbolism was still apparent: the salmon pulled from the river represents a close friend who died suddenly with the moving line: “Nobody knows when you’ll go, And no one thinks to tell you”.

Yet, Lau embody the spirit of jazz in their improvisatory performance style. There is no drummer, and I found the music most thrilling when the rhythm was provided by the virtuoso fiddle player Aidan O'Rouke. Thanks to Martin Green, there is also strong bass energy: he multi tasks, controlling the electronics alongside stunning accordion playing. The innovation in their progressive folk is so refreshing, though in songs like Throwing Pennies I thought the volume of Martin's samples was intrusive: on the album, they're more subtlety integrated into the mix. With this minor exception, the sound, and lighting was excellent. The venue added to the theatrical atmosphere: there was no lack of drama, despite the economy of forces. It was a cerebral experience, a delight for the introvert: outward interaction with the audience was limited to Martin's humorous interjections, and a rare cheer from the audience towards the end.

Lau's invention is inspried by the open spaces of the Scottish Isles. Torsa, an early highlight in the 90 minute set, evokes the landscape of an island south of Oban that Aidan knew as a child; whilst Kris was born in Orkney and has now migrated even further north to Shetland. They're steeped in Scottish culture, yet transcend geographical boundaries: a song like the closing Far From Portland evoking a universal tenderness and aching beauty. A sense of traditional culture doesn't preclude complex layers of sound, just as beauty doesn't imply a lack of dynamics. Their virtuosity can be exhilarating, the volume of the trio thunderous one moment, delicate the next. Lau also sends a message about collaboration: far from being dominated by a lead vocalist, their appeal is in the thrilling interplay. This collective spirit embodies the fact that in remote communities, interdependence is a essential to survival; too often in urbanised society the need for co-operation is overlooked. Yet, Lau is forward thinking as well as nostalgic in providing a window on a world of alternative values, informed by our connection to the natural environment and the need for mutual bonds. Even if you're not naturally drawn towards Celtic folk trios, I urge to explore their music, and performances.