HOWZAT

Grossman says age doesn’t matter either. “Every time you open the paper it seems that bands who appeared to be grown-ups when I was a lad are touring again — the Rolling Stones, the Police, Pink Floyd. We’ve got used to seeing greying guys up on stage wearing jeans.”

And as for social class, he agrees that people care less about that too: “The Crewe by-election was by no means the turning point, but it was symptomatic of everyone having better things to do now than worry about class warfare. I have long held the view that the less you know about a performer the better. I honestly don’t really want to know where any musician went to school or what his parents did.”

People used to care hugely — the Marquess of Worcester, known to his chums as “Bunter”, has had a band called Planet Potato for donkey’s years, but it’s never made it beyond the pages of Tatler. Crispian Mills of Kula Shaker, the grandson of the actor John Mills, used to get ridiculed for being a posh wally. Louis Eliot, the really hard-working musician son of the Earl of St Germans, is still gigging, but enjoyed only limited success in his Britpop youth with the bands Kinky Machine and Rialto.

Once, Genesis and the Clash would be told to play down their public school education (Joe Strummer claimed he went to “a sort of private comprehensive” — it was City of London Freemen’s School). But James Blunt’s PR people decided to use his Sandhurst background as his USP, rather than hide it. Our nation’s biggest acts — Coldplay, Razorlight and the Kooks — all have privately educated singers.

Up-and-coming bands include Mumford and Sons, whose Marcus Mumford is an Edinburgh classicist described to me by one of his quite posh friends as “the poshest man I have ever met”. His musical style? Bluegrass, of course — the folk music of poor white America.

On the clubbing scene Henry Conway, a son of the disgraced Tory MP Derek Conway, fronts a club night at the Mahiki Club in London and says that Blunt has dropped in a few times. “He’s an old friend,” Conway says. “I suppose he’s the pinnacle of the new scene because he’s Harrow, Army and proof that the music wins through. Once it would have been hard to imagine that anybody like that would be a success in England, but now it’s so anti-cool that it’s cool.”

Then there are the DJs: Isaac Ferry, the son of honorary toff Bryan and brother of the fox-hunting campaigner Otis; John Lycett Green, son of Candida and grandson of John Betjeman.

The rise of the boutique music festival has brought many stately homeowners into the pop music arena too — the Secret Garden Party is run by the son of Baron De Ramsey in the grounds of their country pile in Cambridgeshire.

Meanwhile the New Forbidden are due to play at the Rebellion Festival in Blackpool in August. Looking at the other bands on the line-up, and then at his bank account full of pasta sauce millions, how does Grossman feel his punk credentials stand up? He laughs. “Well, I don’t call this punk anyway,” he says. “It’s more indie, garage rock.”

Their excitement about the gig is palpable, though. I ask Guinness if he has ever been to Blackpool, spiritual home of working-class beach holidays and the cheap amusement arcade. “What do you think?” he asks with a self-effacing smile. “I have been looking forward to visiting Blackpool all my life.”

Second Person’s single Wood is released on Aug 11. They play Pizza on the Park, London SW1 (020-7235 5273), on July 2 and at the Indig02 on July 30. www.secondperson.net.

- The New Forbidden play the Rhythm Factory, London E1 (020-7375 3774), on June 26 and the Rebellion Festival in Blackpool on August 9

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