The most expensive and rare musical instruments in the world are on sale at auction in South Africa and the world is talking about them.
How do they work?
How do you know when you’ve found the perfect instrument?
How many do you need?
All this and more on BBC Sport’s auction of the century, where the best musical instrument in the country is on sale for the first time.
The auction takes place in Cape Town on Monday, the day after the Queen’s Diamond Jubilee and before the start of the Rugby World Cup.
It will be the biggest ever auction for a musical instrument.
The sale will start at 10am on Monday and run until 10pm.
“I am really excited about this auction,” said Peter van der Merwe, the head of the auctioning department at South African auction house The Hague Auctioneers.
“It will be an opportunity to see some of the world-class instruments and their history.”
Most of the instruments on display in this year’s auction are made by the Danish company Dansk Musikar, and the most valuable are the Eureka, the first violin made in Denmark in 1589.
Dansk was bought by Dansk-Musikar in 2009 for more than $1.5bn.
The violin has a weight of 2.3 tonnes, and it was made by a master violin maker, Johann von Eiener in the early 18th century.
It was sold for just $1,400 (£965) in 2014.
“The Eurekahs are really unique instruments,” said John Toulmin, who runs the auctioneers’ website.
“They are a great example of the way in which art and craftsmanship are interwoven.”
The first violin to be made in the Danish style was made in 1482 by Hans Peter Nielsen, who died in 1518.
“These are really rare instruments,” he said.
“This is the first one made in Danish and it is a rare piece.
I don’t know why we have such a high price tag.”
The auctioneer said the Eucharistic Triumph, a rare violin made by Danish artist and composer Hans Christian Anderson, is the best-known Eurekatone violin in the auction house.
The Triumph is the only Eurekas that have survived the centuries.
Its maker, Johannes P. Van Oerth, died in 1873 and was buried at his home in Ghent, Belgium.
The most famous violin in South African music is the Eustachian Triton, made by Johannes Goudsmit in 1775.
The Tritons are still made, although they have been out of production since the 1970s.
“A lot of people have bought the Tritones,” said Mr van der Meerwe.
“For a lot of us it is an opportunity for us to see the world through his eyes.”
The Trieschner-Langbauer Trio, which includes the violin, the flute, the viola and a piano, sold for $6.3m.
The Trio includes two instruments: the flutist’s flute and the flumperbock.
It has a total weight of 7.7 tonnes and was made for a man named Johannes Vergens.
It is the most expensive violin in its class.
The second-hand violin was made to celebrate the 20th anniversary of the recording of the German song, “Eine Einheit”.
It is made by Johann Peter Duscher in the 1800s and was sold in 2014 for $1m.
“Duscher has been a great collector,” said Richard Visser, the director of the Duschner Foundation, which owns the Trio.
“His music is wonderful and the Trios are very important to him.”
The Eurekkas are made to be played at a concert hall, and their range has grown to include music by Johann Sebastian Bach, Johann Sebastian Grieg, Johann Wolfgang von Goethe, Friedrich Schiller, Anton Bruckner and the great composers of the 19th and 20th centuries.
The best-selling instrument in South Korea is the K-pop idol group Super Junior, which has sold over 60,000 K-solo instruments since its debut in 2012.
The K-Solo instruments are made in China and sell for more $600 to $900 (£420 to £480) each.
The instruments are used in the music videos of the group’s members, including Super Junior’s song “I Will Love You”.
“The K-League’s music videos are just amazing,” said Taehyun Kang, the group, which is made up of four members.
“Everyone here has really good taste.
The video team is very creative.
We like to have fun with it.”