Most of his competitors were 10 years older but the young Hongkonger, who conducted Prokofiev's Third Symphony for his final piece, struck a chord with the judges. 'I think they were looking for a completely musical person; I was glad I was able to bring that side out,' he says.

Such expression is key to the role of a conductor, So says. 'It's understandable that only the discerning ears can hear the difference, but I'd say a conductor is successful when the music can touch the people's hearts.'

Former winners such as Vasily Petrenko and Tugan Sokhiev have gone on to impressive careers. However, So says he entered the Prokofiev competition mainly to learn from top musicians. 'I didn't set out to win because personally I don't think it's a very good attitude to have,' he says.

So has a reputation for immersing himself in his orchestra's music and has been faulted for wiggling his hips on stage, but he says he can't help it. 'I am easily captivated by good music and I'd completely forget myself.' But some judges like conductors who don't care how they look, he says.

There's more to conducting than waving a baton, So says. 'You can learn the basic conducting skills in a couple of hours, but it is a life's work to interpret the scores and get into the minds of the composers.'

Describing himself as having a 'knowledge-lust', So reads history, philosophy and literature as well as scores to gain a deeper understanding of the human condition and its interpretation in music.

'To bring good music to people, you have to broaden your horizons,' So says. 'I have a natural curiosity about what's happening around the world so I can understand what the audience needs and wants. A conductor can speak for those in need of emotional support and fulfil their needs with music.'

No musical snob, he also enjoys artists such as Radiohead and Bjork, saying, 'They are very interesting because they prove their mettle as real artists.' But he adds: 'The value of music shouldn't be measured by how much it can sell; if that's the case, there'd be less and less good music around.'

So displayed a sharp ear for music even as a toddler. His father, a developer, and his mother, a teacher, were happy to nurture his talents and he soon learned to play the piano, viola, violin and pipe organ. He also sang and composed a musical when he was 13. But conducting captured his heart, and without any push from his parents, he says. 'I decided on being a conductor because I don't think I can play any of the instruments better than others,' he says. 'I think I have some great ideas about music, so being a conductor suits me best.'

So, who was named the Post's 1996 student musician of the year, first took to the rostrum when he stood in for a teacher and has been hooked on conducting since. He spent a year studying philosophy at Peking University, then earned a degree in comparative literature at Yale University. But the years of studying dense German literature left him under a pall and it took him more than a year to work clear of 'depressive tendencies'.

He found his calling training as a conductor at the Peabody Institute of the Johns Hopkins University, under the tutelage of baton masters such as Gustav Meier.

'When you're up there [on the rostrum], you have to bring out your personality and communicate your knowledge of the score through your face and body. It takes a long time to master this. You have to have charisma and a way with people by showing humility and appreciation. Be demanding without being condescending,' he says.

'It's also challenging to keep it fresh and discover something new in a composition that you have conducted more than 30 times.

It's a constant struggle to capture that feeling.'

Still, there were moments of frustration and self-doubt.

'I couldn't seem to break out or find a job,' So says. 'It looked like I was doing the right thing but I was not sure if I could show that my heart and mind were connected.'

After graduating in 2006, he served as resident conductor of the Hong Kong Children's Symphony Orchestra for about a year, and later hosted radio and TV music programmes on RTHK and edited an affiliated magazine.

'Hong Kong is my home and I want to see what I can do here,' he says.

'There's something explosive about classical music. It's exhilarating. Classical music is not just for the privileged. I'd like to see it happening around the world,' says So, who is a music director of the Yale-China Music Exchange, which organises Chinese and American students who bring music to the mainland heartland.

Some classical musicians regard the Prokofiev contest, which was launched in 1991, as less prestigious than other more established competitions, but Hong Kong Philharmonic Orchestra chief executive Timothy Calnin says winning the prize will bring So significant international attention.

Prospects seem promising: So will return to St Petersburg for the International Musical Olympus Festival, when he will work with 2005 Franz Liszt Piano Competition winner Teo Gheorghiu and Petrit Ceku, who won the Pittaluga Guitar Competition in 2007.

Meier has high hopes for his former pupil. 'Perry always surprised me with his knowledge and his ability to express himself clearly and convincingly,' says the veteran conductor. 'The talent and the drive is there and it will be interesting to watch him go.'