When did you start singing?

My grandmother was a contemporary of Shirley Bassey in Wales and my mother has a lovely voice, though she’s never pursued it professionally. My first performance was when I was four and I was offered first choice of parts for Peter Pan. I didn’t choose Peter Pan or Wendy, I chose Nana the dog – but I did steal the show!

What was your first paid gig?

I was 16 and it was with an Abba tribute band in a working men’s club. I think I got paid £40, which at 16 is a lot of money, although by the time we’d paid for our outfits and the sound equipment and stayed the night we made a loss.

When did you settle on the idea of becoming a classical singer?

It just came so naturally for me. When I was really small my parents came in to school and the teacher said most children sing nursery rhymes but your’s sings opera. I never really realised I could make a career out of until I was about 14, though.

Were you equally enthralled by the idea of being a pop singer?

Yes, for a while, because when I was a teenager and everyone was listening to Missy Elliott and I was listening to Mozart, I just wanted to be cool and one of the gang. Also, opera training is incredibly expensive, so I did pop auditions from the age of about 15 until I was 19.

Tell us your Gary Barlow story!

OK, so I knew he had just started a record label and as I didn’t really like the idea of working for a business-driven record label, I thought: who better? I took him a demo every day for six weeks. He finally listened to it on a Friday, met me on the Monday and signed me right then.

That’s a heck of a big break.

Yes, but I think you make your big breaks; I’d been auditioning for five years at that point. My friends were going out on a Friday night and having a great time while I was at home preparing for auditions. I think you make your own luck.

You’re what’s known as a “coloratura soprano”. What does that mean?

It’s the highest and most athletic voice type. If Mariah Carey was an opera singer she would be a coloratura. We’re quite rare – you’re born a coloratura; you can’t make one.

What’s a typical performance opportunity for a classical singer?

I try to spread my time between my personal life, my charitable work and paying gigs that make all the rest of it possible. When I first got signed I worked blindly to sell tickets and records and it was amazing but I think if you’re not giving back, it can leave you feeling a bit hollow – and it did. So if I sing somewhere like Cannes or for a big bank, that allows me to come home and do three charity shows for free.

What have been some of your biggest gigs?

Well, the first time you do Wembley is always terrifying, but I don’t know if that was the biggest. The first time I did the Epsom Derby I didn’t know much about it: I knew The Queen was going to be there but at that point I had already sung for her a few times, so it was nerves I could cope with. What I didn’t know is that there were about 150,000 people there as well, plus a massive global audience on TV. But I guess that means there’s no time to get terrified.

Do you have nerves?

I’m quite lucky because my mum is a doctor of psychotherapy and hypnotherapy and that has helped. Now that I’ve been doing this quite a long time, whenever I have a really big event I just practice so much that nothing from my end can go wrong. It also helps to remember why I’m doing it and how much I love singing.

What was the performance from hell that still makes you wince?

Some are just bizarre. Like you might have to get changed in a broom cupboard because sometimes people will book you and pay all this money but don’t think about the fact that you soundcheck at 5 and then don’t perform until 8 and it might be nice to have somewhere to sit for a few hours. Another time I nearly nearly knocked myself out when I was on the BBC TV show Songs of Praise. It was a school choir special, the song ended, and as I walked off stage they were lowering a set and I smacked right into it.

Are there things you have to do to keep your voice in tip-top condition?

You have to be so fit, physically – even the bigger opera stars are fit; Pavarotti worked out all the time. It’s very physically challenging and you’re working every muscle in your body. Girls will come off after an opera and will have burned 2,000 calories in one show. You also really have to take care of your voice, so if I have a big show on a Wednesday I won’t go out from Monday because if I talk too much I’m going to lose all my top register for my performance. It can be very asocial.

Can you shatter a glass with your voice?

I’m sure that I could, however the difficulty is finding the right frequency of the glass, and you have to then project it back to the glass loudly and for long enough to make it shatter.

Have you ever sung in the UAE?

Yes, in Abu Dhabi twice and I used to get taken to Dubai to sing a lot. The people [are] so welcoming and so kind, so it’s something I really enjoy.