First Aid Kit, Thursday 18th of September, 2014 at The Olympia Theatre

These two sisters have come a long way from the two we saw in that astounding YouTube video six years ago, nailing a Fleet Foxes song.

But somehow, despite stardom, critical acclaim, and hanging out with Conor Oberst and playing shows to Paul Simon, the Soderberg sisters still carry a certain sweet geekiness.

Don’t misinterpret what that means, Klara and Johanna Soderberg are still engaging and very much in control of their crowd but there’s a sort of innocence in their performance.

Like any artist, there could be a fear that the sisters’ vocals might not translate so well from the recording studio to the stage.

From their early EPs as teenagers, their music has been laced with intuitive close harmonies that you imagine only siblings can really muster.

Well, they lay that question to bed pretty damn quickly when they appear onstage – and for an hour and 20 minutes you simply can not find fault with their voices.

They are spot on throughout the night, never more so than in Ghost Town, a single from first full album, The Big Black and the Blue. They perform it without any mics, and the crowd chorus a gorgeous a cappella version.

Their stage patter, delivered in perfect American-accented English, consists of the two interrupting each other almost constantly, and yet they remain cohesive and coherent.

A moody rendition of Jack White’s Love Interruption follows which soon builds into an extended build-up under blue lights where the pair play The Lion’s Roar which could be the most heart-stopping moment of the evening.

It could all end there perfectly, but the sisters return for a three song encore.

The night was full of clichéd pin drop moments of quietness, with a crowd giving nothing but respect to the sisters ethereal and melodic vocals.

A pleasant evening of beautiful music and rapturous applause come to an end in the Olympia as the sisters bring another quirky folk inspired set to a close.