Kings of Convenience, Queen Elizabeth Hall, London

Famed for their subtlety and sensitivity, today's most celebrated acoustic duo are naturally compared to Simon and Garfunkel, but in this show they were more end-of-the-pier comedy act.

Famed for their subtlety and sensitivity, today's most celebrated acoustic duo are naturally compared to Simon and Garfunkel, but in this show they were more end-of-the-pier comedy act. You can't imagine Art dancing like your tipsy uncle at a wedding, but there was the gangly Erlend Oye, all geek glasses and shock of orange hair exploding from his high forehead.

The darkly handsome Eirik Glambek Boe was more introvert, but he nevertheless delivered dry, withering put-downs: "This song goes back to living..." Oye began, to introduce a number. "It's a true story," Boe interrupted, eager to crack on. It was a reversal of the duo's emergence three years ago, when Oye was the front man.

At that time, Kings of Convenience were the hardline faction of a new acoustic movement that threw up Turin Brakes and Ben & Jason. The title of their debut album, Quiet is the New Loud, was a defiant if understated two fingers to detractors. After that, Oye guested with his fellow Bergenites Royksopp, before recording Unrest, a collaboration with leftfield dance producers. Boe stayed home to complete a degree in psychology.

On their current album - perhaps unsurprisingly, as it is called Riot on an Empty Street, - the duo have picked up where they left off, albeit with a softened stance that has allowed the odd cello or trumpet to fill out their sound. On stage, the only accessories were drums and grand piano, although the duo began with just their guitars. It was an effective combination as Boe's fingers picked out rhythms on nylon strings, veering from traditional folk patterns to chirpy bossa novas, while his partner stuck to starker melodic lines on a steel-strung instrument.

When Oye moved to the keyboard later in the set, it was to provide more of the same with precise arpeggios. Their harmonies wrapped around each other in an even more intimate fashion, especially when they sang a cappella.

The arrangements, though, were just the pleasant background for their singular songwriting. The Kings are obsessed with not emotional blacks and whites but the grey palette of confusion, misunderstanding and hesitancy. The crowd loved it, especially vintage numbers such as "Toxic Girl" ("The moment conversation stops, she's gone - again") and "I Don't Know What I Can Save You From", with the girl for whom Boe "wouldn't mind to put the kettle on". They needed the humour. It added colour to the set.

By the end, their objective analysis was starting to grate, so it was a relief when their last single, "I'd Rather Dance with You", brought with it a propulsive drumbeat. Oye dived into the stalls to drag people to their feet, causing a rather polite charge to the front. It was a rare example of the duo performing against type, and all the more welcome for it.