Raised in Australia, he started playing the piano at the tender age of four.

His Polish-born maternal grandfather, Henry Masel, was an amateur violinist and his mother, Daidre, imbued him and his brother, Leo, with a love of music.

But it was Geoffrey who went on to forge an immensely impressive career, appearing with orchestras around the world, as well as setting up and running his own label, Cala Records.

For the record, Leo is now a professor of economics in California.

Cala Records celebrates its 25th anniversary this year and will mark the momentous occasion on Tuesday, April 14, at the Reform Club, London.

The event will also mark the release of two new Cala CDs, Cool Brass and Hot Brass.

The CDs feature more than 100 leading London musicians in renditions of jazz, Latin, film, show and popular music.

And 10 of them, led by renowned British jazz pianist Gwilym Simcock, will perform on the night.

The evening will be co-hosted by the Arts Global foundation, with which Cala collaborates in recording emerging young artists of the highest calibre with the aim of bringing about social change through music.

Geoffrey told me from his London office: "I am proud we have kept our label alive.

"Cala is not just a record label for Geoffrey Simon - it is about artistic people who have something to say in their records."

But London is a far cry from Adelaide, southern Australia, where Geoffrey was born.

His father, Leo, was born in the now-Ukrainian city of Lvov and emigrated to Australia, while his mother was raised in Melbourne.

The family moved to Daidre's native city when Geoffrey was six, as his father felt there would be better job opportunities there.

His father later became the founding professor of the School of Building at the University of Melbourne.

Geoffrey recalled: "I had a middle-class upbringing. Australians are very conscious of the world around them, but we also feel safe and cocooned from the rest of the world.

"By the same token, we grow up knowing there are also opportunities elsewhere."

It was that zest for adventure which led Geoffrey to leave Oz and move to New York City, where he studied cello at the prestigious Juilliard School of Music.

Prior to that, he took a degree in piano performance at the University of Melbourne.

"When I was 12, I was put behind a cello because the school orchestra needed someone to play it," Geoffrey explained.

"I loved the sound of it and that was my entrée into ensemble music.

"My parents saw I had a passion for the piano and cello and encouraged it."

Once in the Big Apple, he became more interested in Judaism, too.

The 68-year-old said: "My father tended to underplay Jewish culture, maybe because he had seen so much atrocity in Lvov.

"We were aware of Zionism and we felt passionately for Israel. Many of my cousins went to Israel from eastern Europe.

"A lot of the professors at Juilliard were Jewish and their wives became my Jewish mothers.

"I began to see the richness of the religious side, although I had always felt culturally Jewish.

"I never experienced any antisemitism in Australia, but I do have a memory of being a little kid at primary school in Adelaide and everyone being given a bible.

"The bible I was given was fatter, as it was the Old Testament. That was the closest I got to feeling any different."

Geoffrey did, however, experience a culture shock in New York.

He explained: "I thought I was a good cellist and had this huge talent, but I had a rude shock at Juilliard.

"Every kid was better than me - I realised I was good in a small pond, but terrible in a big pond.

"I decided to stick with it though and Juilliard was where my skills began to develop."

In 1969, he ventured into small-town America when he moved to Bloomington, Indiana, to study the cello at Indiana University.

The same year, he founded the Bloomington Symphony Orchestra, where he was also its music director.

He went on to study in Graz, Austria, as he realised "a true musician had to go to Europe".

Not even 30 years since the end of the Second World War, Geoffrey experienced an uncomfortable moment while in Austria.

He recalled: "One day, a woman took me aside and told me to watch my back, as there were a lot of Nazi sympathisers behind closed doors.

"I also had a girlfriend whose father had been a Nazi.

"My temperament, musically, wanted to be more versatile, which just wasn't possible in Austria."

So he chose the UK and headed to London in 1973.

Geoffrey began to make his way in conducting circles and became conductor and musical director of the prestigious Jewish Zemel Choir.

He has also conducted the London Philharmonic Orchestra, the London Symphony Orchestra, the Philharmonia Orchestra, the Royal Philharmonic Orchestra, the London Chamber Orchestra and the English Chamber Orchestra.

And, in 1974, he finished runner-up to Simon Rattle in the John Player International Conductors' Award.

With the Zemel Choir and the London Symphony Orchestra, he conducted Sacred Service, which featured the music of the late American Jewish composer Ernest Bloch.

While in London, Geoffrey received a job offer from the University of Wisconsin, Milwaukee, to become professor of music, which he accepted.

He flitted between London and Milwaukee for four years, before spending two years at North Texas State University.

In 1984, he was introduced to retailer Stanley Marcus at a Viennese ball fundraiser for the University of North Texas.

Marcus was receptive to Geoffrey's idea of creating The Neiman Marcus Classics - three volumes of double CDs, recorded with the London Symphony Orchestra, Philharmonia Orchestra and English Chamber Orchestra.

He recalled: "They were to be uniquely packaged as a luxury coffee table item, suitable for marketing through the Neiman Marcus Christmas catalogue and also the network of Neiman Marcus stores across the US.

"I was given a large order by Neiman Marcus, which enabled me to engage the three orchestras and, over the next two years, record, produce and manufacture the series.

"It was my first venture into independent CD production and I found it exciting and rewarding - not least the artistic freedom I experienced in deciding on the repertoire and working with the orchestras, soloists and producers."

Geoffrey added: "With these CDs in hand, I repackaged and rebranded them more conventionally as The Cala Series in 1987, intended for the general market.

"They struggled in a world which, by then, was full of super-cheap compilations.

"But it was a good learning experience, and as such the series was the precursor to Cala Records."

Setting up Cala in 1990, Geoffrey recalled: "I recorded unknown music from well-known composers, such as Tchaikovsky, Respighi, Borodin and Mussorgsky.

"I felt CD buyers wanted something different, as well as a credibility when it came to the integrity of the performance."

Over the years, he has also brought together ensembles of single instruments, such as all violins, violas and cellos, for different albums.

Cala's The London Violin Sound, for example, featured 48 violins.

Geoffrey, who has also performed for Queen Elizabeth and conducted the Israel, Moscow, Munich and New Japan philharmonic orchestras, is also a committed opponent of the boycotts, divestments and sanctions movement against Israel.

He continued: "I remember being at a concert by the Jerusalem String Quartet at Wigmore Hall.

"There were demonstrators outside trying to stop people going in.

"I went outside and laid into them, telling them, 'how dare you attack Jewish music and politicise it'. It really is philistinic."

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