A computerised orchestra which can follow the instructions of a real conductor is being heard for the first time in Wales this week.
Glyn Paul clicks on the computer's mouse in time with the orchestra
The system has been invented by Australian opera singer and musical director Glyn Paul, who can vary the speed of the music by clicking on the computer's mouse.
The virtual reality orchestra is accompanying a production of Bizet's Carmen in Cardiff.
Hiring a full orchestra can cost up to £5,000 per night, and Opera Mint Wales, who are performing the opera, say the invention has saved them a great deal of money.
Mr Paul said the system is unique as it has overcome the problem of getting the 'orchestra' to follow the conductor.
"Previous experiments with electronic music have failed because of the problem with beating time," he said.
"The virtual reality orchestra has solved that problem.
"The conductor beats time and I control the orchestra with the mouse according to the beat. I can vary the speed or stop and start like any orchestra.
"I don't know of anyone else, anywhere in the world, who has succeeded in this so far."
The full orchestration of Carmen is stored in the computer and is based on samplings of real instruments.
Mr Paul said the virtual orchestra always played the right notes in the right places, adding that this was something "a real orchestra can never guarantee."
Peter Eswood is the Head of Strings at the Royal Welsh College of Music and Drama, and conducts the college symphony and chamber orchestras.
He said that a computer system could never replace music performed live.
Singer Zoe Challiner: "I think the idea's fantastic"
"There's something very exciting about seeing an opera with a real orchestra," he said.
He added, however, that orchestras could be expensive.
"The computer does open up possibilities for amateur musical societies, but there's always the danger that musicians could lose out," he said.
"This country should pride itself on the quality of its musicians."
Opera Mint Wales has already performed the opera twice in Wales, but Hannah Jones, the Arts Editor of the Western Mail, did not attend.
She said: "It's like classical karaoke.
"It would be very bizarre to go to an opera and see a bloke there with a computer. Very weird."
She added that she would prefer to watch a real orchestra.
But Zoe Challiner, who is taking part in the performances, said: "I think it's fantastic.
"It's brilliant for us because as a small company we don't have the money to pay for a full orchestra.
"So we either have to get a smaller one, or use a piano, which isn't as good."
Opera Mint Wales will perform at the Paget Rooms in Penarth on 20 July.