Developing a strong operatic voice is a physical process. The stress on the muscles must be closely watched. If the chest, neck or throat muscles are used in the wrong way it throws the balance which is the most important ingredient for the singer, he said.
The voice is just 10 per cent of what a successful opera singer needs, he said.
"There are many good voices, but it takes endless hard work, an open-minded attitude and a clear focus to be successful. As the great Italian operatic tenor Carlo Bergonzi said, the voice is just 10 per cent of the overall package."
Young singers from all over the world apply to the international academy in Cardiff, O'Neill said.
"We get dozens of applications but there are also young singers recommended to us.
"For instance, Dame Kiri will contact me and say there is a particular young singer I should listen to."
However, for some singers O'Neill can't audition them in person.
An example is the Pati brothers, Pene and Amitai, from South Auckland who were students at the Wanganui opera school in the past three years. They are studying at the international academy.
"I couldn't just head off down to New Zealand so I needed to listen to more than one tape of their voice."
O'Neill said the runaway success of the brothers' CD O Sole3 Mio where they perform as a trio with cousin Moses Mackay, also at the academy, has been a phenomenon.
"A trio is quite unusual."
O Sole3 Mio is the result of a Universal Music Group talent scout spotting the three singing around Cardiff to earn money for rent and tuition. It's a mix of easy listening songs and opera aria.
O Sole3 Mio's success has undoubtedly helped the boys with their tuition fees, which is marvellous, said O'Neill, but concentrating on their voice tuition is imperative.
"The thing is, these boys have a real presence."
Being personable is integral for an opera singer, who not only sings but acts and needs to have a commanding stage presence.
"And this presence can't be learned ... the performer needs to have it naturally, and you can see whether someone has from when you first time meet them."
He laughed, saying his father, a doctor in the small Welsh village of Pontarddulai, south of Swansea, had deliberately placed his desk and chair in his office as far from the door as he could.
"Which meant, of course, patients had a rather long walk across the room to reach him, and in those few seconds my father was able to form a first opinion from their demeanour as they walked toward him."
Singing has been second nature to O'Neill since he was a small boy.
"Musicality was encouraged in the village by everyone, and if you had a good voice you were always singing in church, at school. . .everywhere."
For a young lad there was always the concern of what would happen when the voice broke at puberty, but for O'Neill his voice remained beautiful and slid with ease from boy soprano to fine tenor.
"I was lucky. It doesn't always happen like that."
He has appeared for all the leading companies of the world. He has specialised in the works of Verdi, having sung 21 of the composer's roles and was awarded the 2005 Verdi Medal by the Amici di Verdi.
He has sung with the Royal Opera House, Covent Garden, London, where his many roles have included Rodolfo (La Boheme), Duca (Rigoletto), Pinkerton (Madama Butterfly), Edgardo (Lucia di Lammermoor), Macduff (Macbeth), Gustavo ( Maschera), Foresto (Attila), Otello, Don Carlos, Radames (Aida), Aroldo, Carlo (Giovanna d'Arco), Jacopo (I due Foscari) and Canio ( I Pagliacci), which was conducted by Placido Domingo.
At the Metropolitan Opera, New York, he has appeared as Alfredo (La Traviata), Rodolfo (La Boheme), Radames (Aida) - conducted by Levine and Domingo - Duca (Rigoletto), Turiddu (Cavalleria Rusticana) and Canio (I Pagliacci). and other North American engagements have included Chicago Lyric Opera, San Francisco, San Diego, Vancouver Opera and concerts with the Philadelphia, Cleveland, Montreal, and Ottawa Symphonies, and for the Cincinnati Festival. He has also appeared in several South American opera houses.
He has performed extensively throughout Europe at opera houses and festivals, but has always had a close and special relationship with his home based Welsh National Opera, Cardiff, where he appears in most seasons and serves as a member of the board.
He said one of his most most memorable concert performances years ago was of Edgardo (Lucia di Lammermoor) at a small hall in Lerwick in the Shetland Islands.
"I had a great time, met wonderful people. It will always be a great memory of a wonderful concert in a very small place."
O'Neill is constantly in demand as a concert artist and said he has been very fortunate because his voice remains strong and resonant.
His deep involvement in teaching young opera singers, has meant he has travelled and given masterclasses throughout the world, specialising in the Italian repertoire and bel canto technique. He also is an adjudicator at many of the world's prestigious international competitions.
O'Neill's commitment to opera and young opera singers is all consuming and he said he is delighted to be in Wanganui in midsummer rather than in Wales in the bleak, grey winter.
"I enjoy listening to all the young voices and to try and help these young singers find themselves and their voice. Collegiate School is beautiful.
"I'm very pleased to be here."
The New Zealand Opera School is in Wanganui until January 19.
lin.ferguson@wanganuichronicle.co.nz
