Danielle de Niese.

Danielle de Niese is a walking, singing, exclamation point, such is her outward vitality and vigour. Photo: Reuters

ON THE cover of Danielle de Niese's latest album, Beauty of the Baroque, the singer's voluptuous figure is swathed and cinched into an off-the-shoulder gown of purple silk designed by Vivienne Westwood. Inside, de Niese models five more creations from the grande dame of British couture: Westwood and her dark-eyed muse are the poster girls for this production — supporting acts by Handel, Monteverdi and others.

"Vivienne loves music," de Niese says. "In fact, that's how we met. She saw me in a concert wearing Donna Karan and she was like, 'Who is that girl? I want to dress her!' Her gowns fit perfectly with my CD — modern and baroque at the same time."

It is almost impossible to quote de Niese without exclamation marks. She leans over our little table in the bar of London's glitzy Langham Hotel with her megawatt smile and huge Kohl-rimmed eyes, exuding enthusiasm for everything from her coming tour with the Australian Chamber Orchestra — "I've heard such great things about them, I'm so excited!' — to her Portuguese water spaniel Caesar: "He is totally brilliant, so smart and he doesn't shed!"

Danielle de Niese, opera singer, Young Talent Time.

The singer, age nine, on Young Talent Time.

She shares Caesar with her husband, Gus Christie, chairman of the Glyndebourne Festival in pastoral Sussex, where the English come to hear opera, drink champagne and get grass stains on their summer frocks — and where de Niese made her 2006 debut as Cleopatra in Giulio Cesare. Glyndebourne had never seen anything quite like the then 27-year-old's dazzling portrayal of the Egyptian queen, the "Bollywood-meets-Bananarama" dance sequences executed with "terpsichorean grace" and the smouldering seduction scenes: "De Niese puts the sex into Sussex," noted an excitable reviewer.

As legend has it, Christie's grandfather built the opera house on his country estate so that his American opera-singer wife need no longer travel to Covent Garden for work. In a neat piece of symmetry, Gus married his own diva in 2009 — the Melbourne-born de Niese is now chatelaine of the 600-year-old manor house — though without any hope of tethering her to Glyndebourne. His wife is an international star with engagements scheduled five years ahead: "I already knew where I would be singing this year before Gus even proposed to me," she says.

At 33, she is stepmother to four boys from her husband's first marriage; are there plans for a family of her own? "I haven't got to the point of scheduling babies," she laughs.

Danielle de Niese.

De Niese laughs a lot, her long-drop crystal earrings bobbing and swinging above a grey silk jersey dress that looks quite Donna Karan. "Oh, I don't know, it might be," she says, obligingly reaching behind her neck for the label. The earrings are by Van Cleef & Arpels, the French label that provides her jewellery.

It does all seem a bit fairytale, the Danielle de Niese story: the infant who sang with "perfect pitch" at 12 months, the nine-year-old winning Australia's Young Talent Time, the career move to the US, where the "Disney Princess", as one interviewer described her, not unkindly, won scholarships and awards and went on to make her debut at the New York Met as Barbarina in Mozart's The Marriage of Figaro at the astonishingly precocious age of 19. Within a few years, The New York Times Magazine had dubbed her "opera's coolest soprano". Now there is the handsome husband, the manor house and the designers courting her favours.

"Of course," she agrees sunnily, "lots of people think I've been handed everything on a plate. But I don't speak too much about the roles I didn't get, the unfair reviews, the times I spent weeping on my mum's lap. I was raised not to be a moaner." Her parents, descended from Sri Lankan, Dutch and Scottish stock, have devoted themselves to her career.

"My mum sang with me right from the start," she says. "She came to every single voice lesson with me, my dad drove us everywhere."

When she was 10, the family moved to California, where there would be greater scope for her talents.

Despite the many plaudits — "De Niese has a voice seductive enough to woo gods as well as mortals" — there have been hints from some opera critics that her alluring glamour may sometimes outstrip her vocal talents. She was "full of stage school charisma", a review of The Enchanted Island at the Met stated earlier this year, "but vocally underpowered as Ariel". Her Beauty and the Baroque CD was "bloodless and blase", according to The New York Times.

De Niese shrugs: "It's the reviewer's job to be critical," she says, and adds: "They hold the bar so high for me compared to people twice my age and I think that's not fair: I'm nowhere near as accomplished as Renee Fleming. Yet."

Her point is that an opera singer's voice goes on maturing into his or her 40s and even 50s. "Mozart and Handel baroque has been my bread and butter and delicious for my voice at the age it is," she says. "More heavily orchestrated pieces require a richness of sound that I'm still acquiring. I am itching to sing Massenet's Manon, for example — I've staged it in my head already — but I'll have to wait at least another five years."

Last year, along with her close-knit team of parents, manager and voice coach, she decided her voice was ready for the role of Adina in Donizetti's L'elisir d'amore: "I put a lot of pressure on myself," she says. "People were waiting to see if I was up to it." Her performance won general acclaim

and for de Niese, her opening night as Adina was a triumph: "Oh my god, I've never felt so strong!" She pumps a bicep and laughs: "I felt I'd graduated to a different weight class."

Next month, de Niese will sing with the Australian Chamber Orchestra in a concert series that includes Schubert's Death and the Maiden and the premiere of a new piece by composer Carl Vine, The Tree of Man, based on the Patrick White novel. It was commissioned and written for de Niese, whose appearance with the ACO is "long overdue", according to the orchestra's director, Richard Tognetti.

"She's an exquisite singer and exquisite looking," he says by phone from New York, where the ACO is performing.

De Niese hasn't read White's novel yet — "It's in the mail, I hope it's not too long!" — but has been studying the music.

■Danielle de Niese performs a national tour with the Australian Chamber Orchestra, 17-25 June, aco.com.au.

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