Every time music fans flock to see their favourite star on stage there is not one performance going on, but two.
There is the one they see ... the rock god strutting his stuff, the musician displaying breathtaking brilliance.
And there is the one behind the scenes – just as carefully choreographed and just as crucial to the show’s success.
So says promoter John Hessenthaler, who has spent his 40-year career pulling together all the strings that make the magic happen.
He has worked with some of the biggest stars, and also put on shows in village halls.
But whether we are talking a megastar and a crowd of thousands, or, as he put it, “two men and a dog” the principle is the same.
There is a background team doing everything from fixing the lighting, to organising portable loos, or indulging demands for white roses in the dressing room.
John began his career in the 1970s running discos in village halls, while still persisting with a very different job more approved of by his mum.
After leaving school he went to work for the former West Suffolk County Council at Shire Hall in Bury where he trained as a land surveyor.
“I couldn’t stand it because it was so stuffy,” he says. “Then I went to the Gas Board, measuring up gas pipes.
“But there comes a point where you make a decision what you want to do and I knew surveying really wasn’t for me.”
Since then he has been very much master of his own destiny.
“I always wonder if I had stuck at surveying what my life would be now. Quite dull, maybe,” says John who lives in Lavenham with his partner Shirley.
Dull is one thing his career has never been. A promoter’s world is a high-octane, rollercoaster ride, but it almost seems as if he never had a choice.
“It’s kind of in my blood, You have good times and bad times. It’s about taking financial risks and pressures,” he says.
“In what I do you learn about loads of different aspects of life ... how nice people can be and how horrible they can be.
“But if you never take a risk you never get anywhere, and believe me, I have taken some risks.
“I’ve hired stately homes where I’ve put on big acts like Elton John and Status Quo and financed it all myself.
“And you’re booking people so far ahead you have think, how popular will they be in two years’ time?”
John grew up in Great Waldingfield near Sudbury, with parents Fred and Vi, and sister Carol who still lives in the village.
“When I began doing the discos in village halls in Suffolk I didn’t realise I was running a business – but even then I was.”
Gradually local bands began asking him if they could perform at the discos.
He moved on to promoting gigs at Bury Corn Exchange where his first big act was punk band The Clash.
From then on it was onwards and upwards booking bands on tour in the UK, Europe and Ireland.
Rock icon Rod Stewart, legendary singer/songwriter Carole King, and chart-toppers like Busted and boy band Blue have all been all on his playlist.
“I’ve done a lot of concerts with Jason Donovan ... he’s a nice guy. You usually find it’s the more sensible ones who last,”he says.
“Some of the bands I was putting on in the 1970s I’m still promoting today.”
They include ever-popular Showaddywaddy, and Hot Chocolate who are still selling out huge arenas 47 years after their first top ten hit.
The line-ups may change, but John likens this to staff changes in a company. “Things don’t necessarily stay the same, and people want to hear the songs.”
“My earliest recollection of putting on a really big band was Showaddywaddy at Ipswich Gaumont.
“It was packed with screaming girls, they were like the Take That of their day. And I put them on again at the Apex in Bury last year.
“I’m sure a lot of these stars never expected to keep going for so long.
“Bands used to say they thought it would last a couple of years then they’d go back to whatever they were doing before.”
Pop icons Rick Astley and Lulu, and rock and blues king Bill Wyman were on the programme the first time John staged Abbeyfest in Bury’s Abbey Gardens in 2011.
He had only crossed paths with Bill Wyman once before, when the then-Rolling Stones bassist was already a massive star.
“When I worked at Shire Hall my boss sent me down to the licensing office to tax his car. Bill, who had just bought Gedding Hall near Bury, was in the queue.”
Sometimes a major celebrity arrives at a gig in a surprisingly low-key way.
“Rick Astley drove himself, so did Shane Richie when he came to Bury last year. He was just there with his band getting things out of the car.”
There are times John sees behind the public face of a music legend and is surprised by what he finds.
“I was asked by an agent to meet Robin Gibb from the Bee Gees, so I went to his home.
“On a side table was a photo of him and (his brother) Barry with Michael Jackson, who had just knocked on their door in LA one night.
“He really wanted to go out and do shows. But he was already quite unwell, and I was struck by how lonely he seemed.”
These days John’s company, OEP Live, puts on up to 500 shows a year – often several on the same night.
Since he started, the internet has completely changed the way promoters and artists work.
“At one time if you wanted to book a band you might write to their agent. Sometimes you would just knock on people’s doors.”
Or randomly bump into them in the street as he did with locally-based Steve Harley outside Sudbury Woolworths.
There have also been a few notable missed opportunities.
Coldplay’s tape lay forgotten on the back seat of his car after the then-unknown band asked him to have a listen.
Then there was the lad from Framlingham whose manager’s email went unanswered. Yes, it was THAT lad from Framlingham.
Ed Sheeran. “Uh-oh!” John says ruefully.
He goes to concerts when he gets the chance. “Bruce Springsteen is one of my musical heroes. He’s still hungry for what he does. That’s like me, I’m passionate about what I do.”
In October John is staging a gig close to home bringing folk rock band Lindisfarne to Lavenhan Church.
Tickets for the concert on October 20 are available online at www.oeplive.com or by calling 01256 416384.