As a bass player, formerly with T Rex and Sky, Herbie, somewhere "over 60 and under 21", knows his business inside out. He plucks chords out of thin air, sees the best in everyone and ignores the rest. "I've done my bit," he says. "Now I want to pass things on."
So on came the band: Malcolm, on drums, whose son Jim, the coolest 16- year-old on the planet, probably, played bass guitar; Nick, Herbie's own son, was sound man; Derek, maestro film-score musician, on keyboards; Mike and Mutley on guitar and Gary, jazz guitar. Kate, 19, and Clare, 18, backing singers with Herbie's real-life band, Pollish, were there to teach vocals, along with Phil Rhodes, 28, lead singer and a kind of chunky Mick Hucknall, with a sense of rhythm that suggested a set of drums beating in his breast.
This was Sunday morning, and the band, on stage in the Barn Theatre, by the beautiful medieval quadrangle at the heart of the college, jammed until lunchtime. Each student had different expectations; Viktor, from Serbia, came to take the format of the Rock Shop, which runs sponsored courses all over the country, to further "cultural reconstruction in the former Yugoslavia"; Sue, a teacher in her twenties, had a huge voice but wanted a boost to her confidence. Then there was the seriously good-looking Mark, an aeronautical engineering student, who just wanted to sing.
All of us fell in love: with Herbie, with the band, with the beat. It was like hearing music in Technicolor, after years of black and white.
"We're going to write some songs," said Phil. "Who's first?" Silence. Except for the sound of chair legs scraping back from the exposed front row. Well, someone had to do it. "OK," said Phil, after the band had put a melody to my tuneless rendering of scribbled lyrics, "we'll do that tonight." "Tonight?" "Yeah, with an audience - practice for Friday's concert." Moral of the story: never volunteer. I'll cast a veil over my live microphone debut.
Linda, a marketing director, bottled out with her song - "False Hearts, Bad Starts"- frightened, she said, that she'd sing the "f" from "false" on the wrong word.
The daily schedule listed the Rock Shop as starting at 9.30am. It never did. "It's so laid back you think nothing's happening," said Gale, a former Labour candidate. "But it is." Among the 27 acts on Friday, all created that week, was my "Lay Down Low" (all I really wanted to do, frankly), but this time it was sort of OK. Kathleen, from Tucson, Arizona, brought the house down with some deep-South blues, and Sue belted out "Ain't No Sunshine".
As we left, we took with us deep satisfaction at overcoming limitations, and a warm sense of being part of something special. It wasn't quite Nirvana, but it did put us on the first steps of our own stairway to heaven. Rock on, Herbie.
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