Keane, University of London Union, London

When BBC News Online ran their "Sound Of 2004" survey of music biz insiders at the turn of the year, the winners - one place ahead of Franz Ferdinand - were a previously unknown trio from historic Battle in Sussex, whose USP was being a rock band without guitars.

Necessity, so the cliché goes, is the mother of invention. And so it is in the case of Keane, the contents of whose Transit van used to be far more conventional until their guitarist quit, leaving them with an unusual line-up of vocals, piano and drums.

There's a frequently posited argument that, with a more traditional armoury of instruments, Keane would be just another Travis (with whom they are touring as we speak), Starsailor (who they have supported in the past) or Coldplay (Keane's recent breakthrough hit, "Somewhere Only We Know" is their "Yellow", right down to a verse which begins "I walked across...").

It's an argument which isn't without its merits. But even if Keane did become stringless by accident rather than design, this immediately makes them more sonically interesting than 90 per cent of their peers.

As with their piano-driven predecessors Ben Folds Five, Keane's songwriter and lyricist, Tim Rice-Oxley, is seated behind the ivories. However, he leaves frontman duties to singer Tom Chaplin.

Assuming the band to be named after footballer Roy, I'd expected Chaplin to display some of the strutting, cocksure arrogance, single-minded never-say-die spirit, and a random tendency to lapse into the extreme violence of Manchester United's ageing midfield pitbull. Instead, the amiable, slightly chubby Chaplin, who bears a resemblance to the young Brian Wilson, actually has a meek, bloke-down-the-pub (or, to be accurate, down-the-Student-Union) demeanour.

There's a simple reason for this: their name is nothing to do with Roy, nor even Tottenham's Robbie, but a certain Mrs Keane, an elderly nanny who used to look after Chaplin as a child. The Mary Poppins world this evokes may not be wide of the mark. The band are almost certainly rich kids: there are a lot of friends and family in the house tonight, and their silk Fendis and cashmere pashminas are considerably more pricey than my own machine-knitted neckwarmer.

This preponderance of what the band's footballing namesake might call "the prawn sandwich brigade" ought to get my Class War hackles up, but Keane disarm me effortlessly.

When they aren't loitering in dad-rock hell, there's a sparkling, delicate quality to Keane which reminds me of the early Eighties likes of Fiction Factory, The Blue Nile, The Lotus Eaters and H20, while "Your Eyes Open" recalls early Simple Minds (note to stragglers: Simple Minds were sublime, up to and including New Gold Dream).

"Everybody's Changing", their once and future single, has a soaring melody ... almost too soaring, in fact (and Chaplin struggles to reach the high notes). This is an old producer's trick, used to add a yearning quality to the voice (and it must be deliberate, because one of the advantages of the piano is that it's much easier to change key).

He knows what he's doing, this Rice-Oxley fellow, clearly the masterly string-puller behind the Keane scenes. Except, that is, for the encores, when his electric piano fails, forcing the band to shuffle sheepishly away.

That's what you get for putting your trust in technology. A couple more hits, and maybe we'll see Keane's roadies struggling onto this nation's grubby rock stages with a giant Steinway grand instead. Now that's what I'd call rock'n'roll.

Keane tour the UK in April and May. See www.keanemusic.com for details

s.price@independent.co.uk