Stuart Skelton is discussing the conclusion to Sibelius’ mighty Second Symphony, singing the theme sotto voce and sketching it out animatedly with his hands.

“It’s probably some of the greatest visual imagery turned into sound that has ever existed,” says the burly Australian singer. “The last movement, it’s just three notes and then, in the coda, right out of nowhere, comes the fourth note you’ve been waiting 50 minutes for. It’s like the sun crowning on a frozen lake with snow-tipped fir trees.”

As he says this, his eyes glisten and his voice momentarily cracks.

Emotion is never far below the surface for one of the world’s greatest living tenors. It’s this passion and intensity that are the hallmark of performances that have thrilled opera audiences across the globe.

For lunch, Skelton, 56, has chosen Cronulla’s Sealevel, a much-loved “occasion” restaurant among generations of locals for more than 25 years. After a few days of downpours, Cronulla is turning it on, with big surf and brilliant autumn light beyond the restaurant’s picture windows. Fittingly, a few tables over, I spot good friends celebrating the 90th birthday of their mother.

For entree, we settle on a dozen plump Sydney rock oysters with a coriander mignonette, followed by barbecued furikake Murray cod fillets, pork belly and a caprese salad.

Sadly (although perhaps not for the Herald accountants), we decide to stick to sparkling water, as Skelton, a passionate oenophile, is temporarily on the wagon in preparation for his upcoming performances with the Australian Chamber Orchestra.

Cronulla is home turf for Skelton. He grew up around the corner in Yowie Bay and his parents still live in the Shire.

He doesn’t recall it being a particularly musical household but, nevertheless, there was a musical seed in the young Skelton – possibly from a talented maternal grandfather. When he was seven, he asked for piano lessons.

“My parents were surprised but happy to encourage me,” he says. “They found me a teacher and I guess I took to it.”

This early facility did have its downside, though.

“I was always the one who had to play and sing Happy Birthday at my own f---ing birthday party and that used to drive me nuts,” he says. “It’s like an architect being asked to design a house at a party.”

When he was about eight, he was dispatched to St Andrew’s Cathedral School in the city where the foundations were laid for his future career.

“I had no concept of what church music was or was not,” Skelton says. “But having that amount of music thrown at you just on a weekly basis – stuff that you’ve never seen and have no reason to know what it sounds like – had to be insanely good training, even if you didn’t realise it at the time.”

But even after that rigorous musical education, becoming a professional singer was still not on Skelton’s radar and he instead went off to study economics and law.

“I probably wanted to be a politician. I’m naturally conservative, always have been. It’s in my nature to conserve things and conserve things that work. I live in the United States, and I’m not a citizen so I can’t vote. But I’ve always said I want the Republicans out of my bedroom and the Democrats out of my wallet.”

However, politics’ loss was to be the opera world’s gain, as Skelton continued studying singing and began to realise where his future lay, particularly after winning a scholarship to study in the US.

Aged just 29, he made his debut in Karlsruhe opera house, singing the hugely demanding role of Lohengrin in Wagner’s monumental opera.

His career blossomed from there to the point where he is now one of the most in-demand tenors of his generation. He has performed in most of the great opera houses of the world with many of the greatest conductors, singing the repertoire associated with the type of voice called Heldentenor.

Literally “heroic tenor” the powerful voice type is intimately associated with physically demanding Wagnerian roles such as Parsifal and Siegfried, as well as the works of Richard Strauss and roles including Benjamin Britten’s Peter Grimes. The full Heldentenor package also comes with a powerful dramatic presence on stage.

As a younger singer, Skelton initially resisted the Heldentenor tag he now embraces.

“I let it become attached to me a lot later,” he says. “To a certain extent, that label gets attached to people before their time, before they’ve grown into it. I think it can be an expensive lesson to learn because it comes with a set of self-imposed – certainly externally imposed – expectations.

“In lots of people’s minds, it takes out a lot of other options. And I don’t think it should.”

One of the classics in the Heldentenor repertoire is the ultra-taxing role of Tristan in Wagner’s Tristan and Isolde. The opera runs close to five hours and for much of that time Tristan is on stage.

Skelton describes singing Tristan as travelling to the end of a vocal rope. “Hopefully,” he says, “the rope starts to fray the nanosecond after you’ve said Isolde! [after which Tristan dies]. Then you can fray all you like. It’s like the Formula 1 engine exploding just after crossing the finish line.”

In recent years, Skelton has made the role of Peter Grimes in Benjamin Britten’s eponymous opera his own. Peter Grimes tells the tragic story of a fisherman in a small community who is eventually harried to his death by the townsfolk.

I’m curious to know whether emotion gets the better of him on stage when singing Grimes and other roles, Skelton answers immediately: “Always.”

“I used to try to think of ways to avoid that being the case,” he continues. “And then I decided I didn’t want to, so I stopped worrying about whether it was going to take me over the edge or not. And I think those performances where I’ve not cared if it broke me are the performances the audience and, certainly, my colleagues and I, have remembered most.”

Inevitably, after performing such demanding roles at the highest levels for some 30 years, Skelton has to face the possibility his body or voice will eventually fail him.

“I sing every performance as if it’s my last show,” he says. “And I have yet to find the edge when I’m 100 per cent well.

“Performing is kind of my life and it would be a very tough decision to stop, [but] it’s a decision I’ll make when the time comes and I’m not above making hard decisions.

“At some point, I will not be able to live up to my own expectation, let alone whoever’s paying me and the audience. And the minute that comes, I will walk away, no questions asked. The minute I can’t do it to what I expect of myself, I’ll stop. There’s nothing worse, I would imagine, than singing one year past your sell-by date.”

Opera, and classical music in general, often appear in a perennial state of hand-wringing over “relevance” and ageing audiences in concert halls and opera theatres.

However, Skelton remains sanguine about the future.

“As much as the music is written by old, dead, white guys, it is still absolutely glorious music,” he says. “And there’s nothing that you’ll ever be able to do to change that. You can not program it all you like, but at the end of the day people will want to hear Brahms and Mahler and Sibelius and Beethoven and Mozart and Haydn, whether they’re dead white dudes or not. That music is timeless, so people will always go to it.”

Skelton’s upcoming engagement in Australia is Gustav Mahler’s epic song cycle Das Lied von der Erde (The Song of the Earth).

In characteristic style, he describes the six songs in the work as five songs of “do not go gentle” (after Dylan Thomas) and the final song as “yeah, f--- it”.

“Which I love, because the f--- it version is half the piece,” he adds. “It’s all bluff and blustering. And then … it’s sort of Dylan Thomas isn’t with us any more. It’s going to be OK. It’s the sunset and it’s John Wayne. You’ll be fine.”

‘As much as the music is written by old, dead, white guys, it is still absolutely glorious music’

Stuart Skelton

And while his operatic career is all-consuming, to the point he rarely gets to spend time at home in Florida with his wife, Icelandic violinist Asa Gudjonsdottir, when he’s not preparing, performing or teaching, Skelton famously likes “mucking about with cocktails”.

“By mucking about, I mean drinking them,” he laughs. “I also like a really good Cuban cigar on occasion, but you really have to pick your time. And I love to cook animals over open flame.”

It all sounds a bit Hemingway. Perhaps unsurprisingly, Skelton is a huge fan (“he writes like a boxer”).

“God bless Hemingway,” he says. “When people say, ‘What’s your retirement plan?’ I say, Hemingway – without the suicide.”

Stuart Skelton performs Mahler’s Song of the Earth with the Australian Chamber Orchestra, Sydney Opera House, May 12, and City Recital Hall, May 15, 17, 18.

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