Last week on Radio 4's Today programme, the teenage soprano Hayley Westenra tried to prove that her stratospheric top notes could make a dog bark. She failed.
The dog barely growled, though her agent must have been purring at the peak-time exposure, never mind his client's red face.
And last week in Milan, world-class tenor Juan Diego Flórez broke all La Scala taboos by encoring an aria so that he could sing his virtuosic high Cs again.
The American-born Nicole Cabell, 29, winner of 2005 Cardiff Singer of the World, is made of different, sterner stuff. In London for the launch of her debut album of operatic arias from Donizetti to Gershwin, the fastrising soprano finds such behaviour deeply embarrassing.
"I guess we all have to work harder to keep ahead of the game," she acknowledges. "Music colleges are like opera factories churning out hopefuls - but there's a limit.
"Singing is not about high notes and acrobatics. It's about telling a story. All I want is to take the ego out of the equation.
"The idea of encoring a top note, or even stopping to take a bow in the middle of a performance after a showy aria - aagh! The very thought. I can't do all that prima donna stuff."
This elegant and articulate Californian clutches her throat in horror at the idea. Still hardly known here, except to those who delighted in her Cardiff success, Cabell is every inch the glamorous star, with a light, silvery voice equally at home in Italian and French repertoire as in Cole Porter.
"I love doing popular American music. That's my heritage. But I'm not a jazz singer. I prefer to do what's written down."
Cardiff has thrust her into the elevated company of past winners such as Bryn Terfel, Dmitri Hvorostovsky and Katerina Karneus.
Her international career is taking off and she has been touted as "the next Angela Gheorghiu", not unreasonably since her first career break came when she stood in at short notice in Berlin for that ultimate celebrity diva, in Roméo et Juliette.
"I did it at a day's notice on only three hours' sleep and with no rehearsal. I've never been so nervous. I knew the role, but I had no idea how my voice was projecting in a new acoustic."
She hasn't yet met Gheorghiu but will sing Musetta to her Mimi in a Chicago Bohème next season.
"Angela can get away with it," she says, tacitly acknowledging that "doing an Angela" has become common operatic parlance for throwing a strop.
"She's a master of the business of self-presentation. It's part of her persona. Some singers are chameleons, always reinventing themselves, like Madonna.
"But by contrast, take Renée Fleming. She's a star, but she deals with it brilliantly. She's much more down-to-earth. Dawn Upshaw is another."
Cabell sees herself more in this Fleming-Upshaw mould, naming those singers as musical role models.
"Maybe it's a lot to do with how you grow up, whether you have to fight to get away from your childhood circumstances, as Angela did in Romania, or whether you're happy with your surroundings and don't need to kick back so much. I had a pretty steady home life."
Her mother, "a stay-home mom", taught Nicole and her brother herself when they were tiny - "so by the time I went to school I was a grade ahead."
Money was scarce but education valued.
So, too, was the sense of community. Her grandfather was the first African-American police chief in Los Angeles, her father a policeman and other members of the family have been FBI agents.
"Yes, you could say we're big on law enforcement in the Cabell family! I wasn't aware of much violence or dirty stuff. I never thought my father would run into trouble.
"There was always a sense of wanting to do well in life. Every time we saw Tiger Woods on the TV, my mother would say, 'Now he's an example to follow'."
This is a reference to Cabell's mixed race, which she perceives as central to her identity.
"It's a case of embracing everything, not saying no to anything. My mother always used to say, when you fill in a form and it asks about race, never put 'other'. Tick the boxes for all the things you are." In Cabell's case this is African, American, Korean and Caucasian, visible in her striking, sharp cheek-boned, perfect oval face.
"I feel that I'm all these races. I'm excited watching Barack Obama, especially since I now live in Illinois. The idea of our own mixed-race senator being a presidential candidate makes me proud."
School music, in the southern Californian town of Ventura where she grew up, was limited. "I played flute in Junior High School, and had a natural musical ability, but it was all marching bands and sport and I thought: no way."
She only started singing at the age of 16. "I was crooning along to Kiri on a CD of my mother's, just fooling around. She was the one who said I really sounded like an opera singer and I should do something about it. I was more into bands like Def Leppard, Guns N' Roses and Nirvana."
She acknowledges that much as she loves the classical music she sings, she does not always find it easy.
"I'm like anyone of my generation. I've got a very short attention span. I have to work hard to get to know the music. I didn't even see an opera until I was at college."
One of her most valuable tools is her iPod, which she uses to help her learn roles. "I play it the whole time and spend a lot of time downloading, mostly CDs because I'm always on the road.
But if I'm not working, I'm as likely to be listening to Joni Mitchell or The Doors. You won't find a singer who'd listen to an opera for pleasure when they've been singing one all day! We need a break."
As she points out, opera was - broadly speaking - the pop of its time, and her appetite for all kinds of music, including rock, remains voracious.
"It's important for any performer to know what's going on, what's current. But it's hard to get Americans interested in opera. They tend to think going to a Broadway show is as good as it gets, culturally. It's so different in London."
How so? "I've heard that glamorous couples wanting a good night out go to the opera and drink champagne!" She is rumoured to be making her Royal Opera debut next season, when she can test out her wild hypothesis.
The surprise is the degree to which Cabell resists the spotlight at all. "Yes, I've had stage fright. But once I'm up there, doing it, I love it."
She always imagined herself as a backroom girl, perhaps working behind the scenes in the film industry, as a writer or producer.
"I'm a real home body. Living in California, Hollywood was always there as part of the backdrop of childhood.
My best thing, if not going shopping, is being in a room on my own, sitting down for five hours and writing fiction. One day I'll go back to it, but for the moment I've got my hands full."
