Ahead of her show at Union Chapel, the singer tells Alex Bellotti why she’s part of a mini musical revolution.

With a kooky aesthetic, a platinum record under her belt and the weight of Sony Records behind her, Australian musician Kate Miller-Heidke had every tool to break the international music charts.

When it came to recording her fourth album, O Vertigo, however, she had a change of heart. Ditching Sony, the opera and pop star asked her fans to fund it, choosing artistic freedom over commercial gain.

Mixing folk balladry, melodic synth pop and her distinctive, acrobatic vocals, the record has been lauded as her best yet, so when she brings it to the Union Chapel on Saturday, will she feel the brave decision has paid off?

“I wish I could take credit for that but it didn’t really feel brave, it just felt absolutely necessary. I guess I just embraced the idea of being a niche artist,” says the 33-year-old.

“Obviously being on a major label comes with lots of bonuses – they’ll probably get you played more on television and radio – but at the same time it can be hard working within such a large mechanism to do cool, interesting things.”

Having initially studied as a classical singer in her hometown Brisbane, the singer has also lent her hand to a series of operas; last year’s The Rabbits at Perth festival and a forthcoming show based on Borges’ The Book of Fantasy are just two illustrations of the modern, crossover style she favours. “As a solo artist, it can get lonely sometimes so it’s nice to work with other people,” she says, but believes there is something special about opera that’s attracting young people.

“The word opera – people have so many associations with it that aren’t necessarily true. Nobody’s out there trying to make more commercial operas – or maybe they are, but I don’t find that very interesting myself.

“There are a lot of cool young people rejuvenating the genre, not from any sense of obligation or duty but because it’s a really intoxicating, distinct art form. It’s a kind of mini revolution.”

The artist isn’t sure what Saturday’s set will consist of, but seems to be embracing her newfound freedom on the stage as much as in the studio.

“There are no rules now,” she says. “Maybe it’s got something to do with the breakdown of the whole system that was so firmly centred around making albums. Now it’s much more everything goes.”

Kate Miller-Heidke plays Union Chapel on Saturday. Visit unionchapel.org.uk