British stadium-fillers Coldplay are heading to Auckland for their biggest show yet. Kitty Empire caught them in Birmingham this week

Key Points:

When Coldplay singer Chris Martin was 17, he went out with a girl called Victoria.

"Well, I thought I was going out with her. She didn't behave like it, let me tell you," he grumbles.

Martin is sitting at a piano on a small, uplit stage set at the end of a short runway, in among the all-seated front rows. His retro military attire is a little frayed; a dubious consequence of the band's love for the raggle-taggle Montreal marching band Arcade Fire.

These being Coldplay fans, no clothes are actually torn in the stampede to get closer to the band's amiable frontman. People even put their phones away when asked to by the stewards. An arena gig by Coldplay is stadium-craft at its most civilised.

After roughly 82 concerts around the world promoting their recent album, Viva la Vida or Death and All His Friends, Martin knows how to shrink the 13,000-capacity National Indoor Arena in Birmingham, in the centre of England, to human dimensions with a cosy piano-side chat about a girl.

He recounts how he went to meet Victoria, armed only with some Cadbury's Mini Eggs, "which, I believe, are made in your city". Birmingham - high on nothing stronger than cocoa and the odd vodka alcopop - screams its gratitude. But Victoria dumped him, the short-sighted minx.

"And I just thought, thank goodness I have a handful of chocolate," Martin winces.

"Think about that when you listen to this song."

The song is The Hardest Part, from Coldplay's last album but one, X&Y.

Birmingham - already softened up by praise for its singing - melts into a puddle at this sugar rush of anecdotal vulnerability.

It is so hard to hate Coldplay, though many have tried. The piano-rock foursome may have been responsible for ushering in a decade-plus of wistful rock, but they cannot be blamed for the sins of Snow Patrol.

Often portrayed as a band racked by self-doubt - "We're not as good as Radiohead, we wish we were Arcade Fire", runs one possible interior monologue - Coldplay give no such impression tonight. It takes some gumption to come on to Jay-Z's I Just Wanna Love You (Give It To Me) followed by a blast of Johann Strauss.

Globally, they have been vindicated again. Viva la Vida is the biggest-selling record of the year (in Britain; in New Zealand they play second fiddle to Duffy). Of late, that nice Chris Martin has even started walking out of interviews he doesn't like, showing a backbone beneath his lambswool exterior.

Tour-hardened but not wearied, Martin bounds around, half drunken sailor, half prize-fighter, charming all the way. The band rearrange a few of their old songs and air most of their newer ones with the added rhythm and bombast a big space allows.

Violet Hill is almost menacing, with its barrage of beats and acid riffing. 42' morphs from a typical Martin piano-ballad into an electronic workout much more bloody than that on the album. While the crowd - and Martin - clearly enjoy singing all the big soppy hits, Coldplay are far more engaging when tinkering with their back catalogue.

The little auxiliary stage is turned into a miniature disco for a techno version of God Put a Smile Upon Your Face. A short segue turns the song into Talk, the tune off X&Y that borrowed reverentially from Kraftwerk. Club Coldplay? Surprisingly, it works.

Coldplay have picked up another trick from Arcade Fire - wandering through the crowd. After a bit of hand-slapping through level one, the band arrive at a third mini-stage set up at the back of the arena, where wheelchairs usually perch.

There, they do Green Eyes acoustically, followed by Death Will Never Conquer. These chummy interludes skilfully break up what might otherwise threaten to become one long mid-tempo soup of hits.

The band's rather more leisurely journey back to the main stage is soundtracked by a thumping rave remix of Viva la Vida. The arena is in complete darkness, lit only by the twinkle of hundreds of dancing mobile phones. It's a properly magical moment, only half-orchestrated by the band's production designers.

When Coldplay re-emerge they re-arrange Politik into a thump of harsh on-beats. But it becomes apparent, as the gig winds to a conclusion, that every feint towards left-field is quickly righted by a band who know where their bread is buttered. The Scientist turns nimbly into Back for Good, by Take That, a band Martin once said they would gladly support on tour.

As it is, Coldplay have just sold out a Wembley Stadium gig next year: their support band is Girls Aloud. Martin's unlikely pal Jay-Z is propping up the rest of the tour.

The rousing Lovers in Japan sees the descent of thousands of coloured paper butterflies, Coldplay's version of the confetti showers and glitter cannons of their fellow arena bands.

Nothing, however, hits a crowd in the soft parts like a wordless chorus. The "woah-oh-oh-woahs" from Lovers in Japan soar around the arena. They even spill out into the night, as fans make their way home along the freezing canal, kept toasty by Coldplay's emotional central heating.

Who: Coldplay.
When and where: Wednesday, March 18, 2009, Vector Area, Auckland.
Tickets: On sale Monday through ticketmaster.