Brian Wilson was sitting in the executive club room of London's InterContinental hotel in 2008, broad forlorn back turned against a bird's eye view of HRH's potting sheds and the Wellington Arch roundabout. "I like peace and quiet very much, I really do. The noise is irritating now, in this room." The young female entourage there with Nelson Mandela were making a fair racket at the buffet counter.

Wilson explained it was lack of sounds – "except crickets, birdsong and wind" – at his California home which helped composition. "At seven, I wash my face, have breakfast – an egg and Kellogg's corn flakes with skimmed milk and Sweet'N Low – and then I sit alone in my armchair, with a leg rest, and put my synthesiser on my lap."

I suggested, because he'd never actually liked surfing or beach life – and because there was a fruit display nearby – that his band might just as well have been called the Peach Boys. "It wouldn't have made much difference to our success," he said. But what about the lyrics? "This is one of the best interviews I've ever had," he deadpanned, pushing his bowl of nuts towards me. "So have some nuts and drink your tea." He recited the song "Tenderly". "...Then you and I, Came wondering by, And lost in a sigh, Were we...". I crunched nuts as he did so.

Back in the day he'd got Paul McCartney to crunch celery and carrots for the track "Vegetables". He'd become obsessed by veg and for a year ran the Radiant Radish shop, before a sedentary life and junk food brought him to "about 311lbs".

Wilson got a 10-minute standing ovation after his live Smile in London. So what length of loud applause would become boring? "Maybe half an hour," he said.