IT was 1982 and young musician Peter Vettese had just come off stage at the city's Learig pub.
Huddled in the Restalrig bar, his friend and band member, drummer Mike Travis, produced a copy of Melody Maker. It would change Peter's life forever.
Mike pointed to an advert for a keyboard player for an "international rock band". It turned out to be Jethro Tull, and Peter - a talented pianist from Livingston - was to get the job.
He says: "I didn't know it was Jethro Tull at the time, but I went for the audition in London anyway.
"I was vaguely aware of them as I had heard them played in my sixth-year common room, but I could never have called myself a fan."
For Peter - who later went on to work with the likes of Annie Lennox, Simple Minds and Foreigner, and has since built an international reputation for himself as a session musician, composer, writer and producer - the audition was a chance to share with Jethro Tull not only his love of music, but also his passionfor the growing trend for synthesizers.
The band wanted to explore their electronic sound, and it was something Peter had already mastered.
He jokes that Ian Anderson, the Edinburgh-schooled "voice and flute" behind Jethro Tull, took pity on him, deciding the "whipper snapper" before him deserved what he called "a few months in the group", although as Peter says: "I stayed for four years. Ian effectively mentored me, introducing me to so many things I am grateful for."
They later went on to collaborate on Ian's first solo venture, Walk Into Light, with Peter co-writing and contributing on keyboard.
Tonight, Peter - who these days is based in London - will return to the Capital to perform for the first time in decades.
He'll play in Princes Street Gardens as part of the Edinburgh Jazz Festival, taking to the Assembly stage with guest star Melanie C, the former Spice Girl, for a one-off gig.
She is the latest in a long line of musicians to have called on Peter for his expertise, and they pair worked together on an album of show tunes she was keen to release following her appearance in the West End hit Blood Brothers.
For the gig, Peter will play music from the mid to late-1970s, along with new compositions written especially for the show, while Melanie C will make an appearance, with Peter as her accompaniment.
"Melanie C is going to sing three tunes from her new album," Peter explains. "She is underrated and is a very classy individual. We get on very well."
How Peter went from Jethro Tull to Melanie C is quite simple - a hunger for all things musical.
After four years touring the globe with the band and appearing on the group's Live at Hammersmith '84 and Under Wraps albums, he decided to quit, eager to try new things and explore other musicians' work.
"It was the evolution of my own spirit," he laughs. "I was massively grateful for the opportunity Jethro Tull afforded me, but I felt I needed to explore other music. I didn't want to close myself in too much. I was young and ugly!"
Music had always been Peter's life. Born into a musical family, he was introduced to a piano aged just four years old. His dad was a saxophonist with a big band, and his siblings all play instruments too.
"I never wanted to be a musician though," he laughs. "Honestly, I wanted to be an astronaut. The thing was, I was already a musician, before I knew it."
Peter is described in the Edinburgh Jazz Festival programme as the "young star" of the city's 1970s jazz scene, a tag he cringes at.
In his eyes he was merely a "participant", just doing what he had always done, playing and enjoying making music.
"You know, I wasn't even aware of a "scene" as such," he says.
"I really was so stupid and dumb back then though, and arrogant. As far as I knew, I could play pretty well and people took me on."
Growing up in Livingston with stints in Midlothian, Hamilton, Wishaw and Brechin, owing to his father's job, Peter was a huge fan of the Beatles, and Paul McCartney in particular.
In 1987, he fulfilled a boyhood dream to play with him as a session musician, but later turned down an offer to be a member of a re-formed Wings, the rock group McCartney had created in 1971 and disbanded a decade later.
"He was casting about for potential members for Wings and I was invited down to his studio in Hastings by one of his producers," Peter explains.
"Paul McCartney wanted to revisit music that had never made the final cut, but he thought was too good to abandon. I played piano and synth and fulfilled a boyhood dream."
Unfortunately for Peter, McCartney decided not to release any of the material and the musician moved on to collaborate with the rock band Foreigner, in America.
Peter says: "Then Paul McCartney's manager called and asked if I was interested in re-forming Wings, and I made a snap decision that the great moment had come and gone.
"I had got to meet Paul McCartney, but I decided my destiny was not with Wings, so I said no.
"I don't know if I did the right thing, but Paul McCartney has gone on to do pretty well without my help, that's for sure.
"I think his manager was just sounding me out to be honest, but just at that moment I was in the Rock and Roll Hotel in Washington DC and I thought I was the king of the world!"
The decision has certainly not held Peter's career back either, having never been short of offers to form partnerships with some of the world's greatest musicians, including the Bee Gees.
"I played with them in 1988 and it was unbelievably awesome.
"As a session musician, I went to their Mayfair studios in London. It was eye-opening to see the Brothers Gibb and the rigorous methods they used to put together material, like cutting up two-track tapes to literally measure the distance between snare drum beats, just to make sure they were right."
The Grammy Award winning arrangement of Annie Lennox's Walking on Broken Glass is down to Peter, as was the 2012 Olympic Games' bid theme tune, Proud, which he co-wrote with Heather Small, of M People.
Speaking about that song, he says: "For eight years it has made us both very proud, having been featured on innumerable adverts, Olympic games and motivational speeches."
So, after all that he has achieved in his career so far, where will Peter go from here? With a list of musical partnerships as diverse as Carly Simon, Cher, Dido, Gary Barlow and former Go West vocalist Peter Cox, who else is there he'd like to work with?
"I can only say what I look forward to - retaining the ability to make music creatively and as a commercial entity. It's always been a privilege."
He adds with a smile: "That sounds so show business though, doesn't it?"
n An Evening with Peter Vettese, in Assembly, Princes Street Gardens, tonight.