Mr du Plessis was a diplomat for 25 years with the South African Government, based in Europe, the United Nations in Geneva and the United States.
"I was selling diplomatic concepts and now I'm selling musical concepts. It's a change in emphasis, but you've still got a product and an audience. It's about passion," he said this week.
"I had a stressful job as a diplomat and this is a passion I want to enjoy doing."
He resigned as a diplomat last year to follow his wife, University of Otago executant lecturer in cello Heleen du Plessis, to Dunedin from their home in Pretoria, South Africa.
Mrs du Plessis started at the university at the beginning of the year and Mr du Plessis joined her in March.
Their two sons, Pierre-Henri (16) and Jean-Jacques (12), are now at school in Dunedin.
"Heleen had followed me around for many years, so it was my turn to follow her," Mr du Plessis said.
"When I got here, Heleen said 'So, what are you going to do?
'"I became a home executive; cleaning, cooking and taxi-driving. I was trying to use my diplomatic skills at home," he said with a self-deprecating laugh.
"But, the boys said: 'Go out and get a job'."
Mr du Plessis comes from a family of professional musicians and studied clarinet "before giving it up for rugby; something I regret to this day".
He also chaired the University of Potchefstroom Choir, organising tours in Europe and South Africa.
"This is such a great opportunity to get involved in the community in Dunedin. I really feel like I'm part of Dunedin now," he said.
"It's a very vibrant society here with the arts and sport. There's always something going on. Being an outsider, I think sometimes people don't see this. They don't see all the advantages here, because they're so used to it. Everything is in Dunedin, actually."
Mr du Plessis praised the contribution of his predecessor, Kate Lovell, who has retired to Wanaka with her husband, Doug.
"Kate did a marvellous job for a long time and I want to build on what she left," he said.
"You have to have a platform and an audience. We want to bring the orchestra and the audience together and build on that.
"It's going to be very exciting. For a product to survive, you have to add new dimensions to it."
