Today Choi is 35 - and his dream has come true; he is a professional conductor and founder of the Pro Arte Orchestra of Hong Kong - a charity that provides orchestral training for musicians under the age of 25.
Last November, he was invited to be the artist-in-residence at the Hong Kong Polytechnic University and hold workshops for students hoping to be conductors.
"To be a good conductor you need to be a good musician first," says Choi. "That way, you can communicate with the other musicians and be their leader."
Good communication is also important. "As a conductor, I want to communicate, not myself, but the composer's message. Understanding the piece - its history and background - is, therefore, very important."
He graduated with a degree in natural sciences from the University of Cambridge, where he was able to develop his passion for music. "There were so many outstanding choirs at the university; I learnt a great deal being around excellent musicians."
While at Cambridge he started conducting choirs and it helped him to focus on a career; after graduating he took a master's degree in instrumental conducting in Indiana, in the United States. After three years of study, he started his working life as a conductor, touring the world with different orchestras. "When I was studying to become a conductor, the first thing my mentor taught me was the importance of collaboration. As musicians, we all want to keep our individuality, but also need to work with others. As a conductor I have to make sure all parts of the music work and sound good together. As a group, we need to listen and respond to the audience, as well. I don't want to dictate to the others; I want to motivate them to give their best."
Choi formed his charity-based orchestra in October 2007 for Hong Kong people, aged under 25, who are talented in music, but may not have the financial resources to pursue their dream. Each year, students can audition to join the Pro Arte Orchestra, which offers free musical training to students and the chance to perform on stage. It began with 50 members and now has 75.
"I don't want anybody to give up music because of financial difficulties. I have seen many talented youths from grass root families and I want to help them to realise their musical dreams. Music can communicate and influence the community. Young people are important in the development of that, so I wanted to create a home base in the community for young musicians.
"I never thought my dream of being a conductor would come true. But it has. So I want to say to all students, 'Dare to dream'."