Owen Pallett, Koko, London

The categorising of music is an increasingly vexed business, and never more so than when filing Owen Pallett under "Pop". If the Canadian virtuoso turned up as one of this summer's Proms' more left-field performers, it would not come as a total surprise.

Pallett is a classically trained musician operating in a pop idiom – a violinist whose sounds multiply through the use of pedals and tape loops until the effect is truly orchestral. Accompanied on stage by a lone percussionist, Pallett is somewhere between Soft Cell and Ralph Vaughan Williams – a wildly romantic figure with a delicate voice, and the creator of entire imaginary worlds – not that the listener really need spend too much time puzzling over them.

This was Pallett's second London show of late. At the Union Chapel in January the surrounds rendered him somewhat austere, if never less than fascinating. Here at Koko, his cabaret qualities came through, and we got a distinct whiff of Kurt Weill and Stephen Sondheim, with a bit of John Adams thrown in as well.

Pallett has impeccable credentials as an arranger and general enabler. He has worked with both Arcade Fire and the Grizzly Bear accomplice, the composer Nico Muhly. Previously operating under the name Final Fantasy (which disguise possibly allowed him to get away with calling one of his albums He Poos Clouds), Pallett has now emerged as himself and just released the remarkable Heartland, a collection of profoundly mysterious and involving songs.

His lyrics are often complex and dark ("I took No-Face by the beak/ and broke his jaw/ he'll never speak again"), and the thrill of his music – which manages to be both texturally rich yet minimalist in spirit – is very powerful.

We knew we were not at a rock concert when someone close to the stage threw something at him – it seemed only playfully – and Pallett, his patience tested, had to explain that his violin was pretty much untouchable. "I was carrying my violin and laptop once and slipped over. It was the laptop I let crash to the ground."

Pallett closed his set with Heartland's crowning glory, "Lewis Takes Off His Shirt", with its compelling refrain, "I'm never going to give it to you", before returning for an encore that included a cover of Mariah Carey's "Fantasy". It's anyone's guess where this extraordinary talent might go next.