YOU have got to admire the person who booked Alt-J for this Oxford show.

Through a combination of judgement, vision and sheer luck, we ended up with an historic gig.

Already possessed of a cult following, the Cambridge band had long since sold out their show at the O2 Academy. And that was before the small matter of the Mercury Prize. Just the night before the four-piece had walked off with the most coveted award in rock for their album An Awesome Wave. Not bad for a band with a symbol for a name.

“So we just won the Mercury Prize,” the band’s Joe Newman announced to rapturous applause from the capacity crowd at the start of the gig.

“And now we are in Oxford and it’s already amazing.”

The band say their ‘delta’ moniker (generated by hitting the Alt and J keys on an Apple Mac) denotes change, and on tonight’s performance that rings true. There is something altogether different about their blend of art-rock, folk, electro and choral harmony.

Playing on a dark stage lit only by an illuminated triangle, the unashamedly geeky-looking lads threw in everything they had, turning in a solid businesslike performance, with little in the way of banter. They simply let the songs speak for themselves. As to what they were speaking about, I’m still not completely sure, except to say it was esoteric – and all the better for it. Newman’s acrobatic voice is a thing to behold – at the same time bluesy and soulful while elfishly playful – used as an instrument as much as a vehicle to convey lyrics. Consequently it is frequently unintelligible. But so what?

The band glide through the album’s high points, with dreamy, ethereal and jittery Tessellate; the cheerier Something Good with its tight, nimble drumming and spacey electronica; Dissolve Me, and Fitzpleasure – its combination of choral harmonies, weird chants, scuzzy guitars and doom-laden scudding electronica encapsulating what makes them so different.

An unsettling and faultlessly executed mash-up of Kylie’s Slow and Dr Dre’s Still D.R.E (Minogue’s lyrics floating over Dre’s instrumental and plodding bassline) goes down well with the crowd, but then what wouldn’t tonight? Liltingly lovely Matilda is next, followed by darkly brooding big hitter Breezeblocks, with its high range vocals and staccato guitar stabs.

After Ms comes the fragile and ethereal Bloodflood, and for the encore, Handmade. They end on the Bhangra-fuelled rhythms of Taro – its hypnotic dhol beats leavened with strings, sending us out glowing into a cold and wet Cowley Road.

It’s over all too quickly – the venue cleared for a clubnight hosted by Annie Mac and her chums. The crowd didn’t care, though. The truth is, we know we got lucky. And we weren’t the only ones. A check on the merchandise stall revealed the band had long before run out of copies of their prize-winning album. It seems their surprise win didn’t only take us by surprise.