Brett Yang and Eddy Chen met at after-school maths tutoring when they were growing up in Australia – now they are selling out international concert venues on their second world tour.
TwoSet Violin, as they are called, is one of the biggest classical music acts online.
With over 7.5 million followers across social media platforms and more than 1.3 billion views on their YouTube channel, the Brisbane duo have shown how the classical music community can bring in new audiences with a little bit of practice and imagination.
The pair, now in their early 30s, are known for their entertaining and informative videos which they started posting on YouTube in 2013.
Their content ranges from mocking inaccurate depictions of violinists in films including 2016's High Strung, to encouraging the biggest classical acts, such as violinist Hilary Hahn, to take part in challenges like playing Mozart while hula hooping.
They even dared to parody South Korean girl group Blackpink for using a small part of a motif from Paganini's La Campanella étude in their song Shut Down. Eddy Chen impersonated the Italian violinist and composer in a video and imagined how he might have critiqued the track.
TwoSet then released a parody track Sell Out which included the lyrics: "I sold my soul to the devil. You sold yours to your label". Paganini (1782-1840) was referred to as the "devil's violinist" because superstitious audiences thought his virtuosic skills were a gift from the devil.
The critiques led to a fierce defence on social media by the K-Pop act's loyal fans, many of whom thought Paganini was still alive. TwoSet later responded with another video, saying it was great to raise awareness of Paganini's work to a wider audience.
Image source, YGImage caption, Blackpink's loyal fans defended the group – many supporters thought Paganini was still alive
When they created their YouTube channel 10 years ago, TwoSet's content was often shared by fellow classical musicians who understood the niche humour of their videos.
They've really broken through in the past few years and now the duo say other classical musicians tell them a wider range of people are coming to their concerts for the first time thanks to TwoSet's content.
"We want to stay true to [classical music's] essence, but at the same time, find ways to connect and meet people where they are," Chen told the BBC World Service Global News Podcast before the London leg of their tour in late June.
- LISTEN: TwoSet Violin on the Global News Podcast (28'22)
They appeared for one night only and it was sold-out.
Molly, from Switzerland, was in the audience to see them perform live. She started watching them as a way of understanding her husband's passion for classical music.
"I'm someone who has never played music in my life, love to listen to classical music and wanted an easy way to learn a little bit more," she told the BBC.
She said she now feels part of the community. "Every video I find out something new. Little by little I thought [I am] getting the inside jokes."
Grade 7 violinist Georgina Hill, who's 14, discovered them in February and said she had been "watching all their videos from all the years back".
For her coming to the show felt like a rare opportunity. "It's really exciting," she said. "It's nice to be new (to the fandom) but it's nice to see people who have known them for a long time and see the spectrum of people. Music is such an important part of life and what we need."
Maud, meanwhile, has followed the group since 2017 and travelled all the way from France especially for the concert as "they were not coming to Paris".
"I like that they make classical music easy to understand for everyone and are pretty fun. Since I play the violin, I like their videos a lot."
Image source, MacamiImage caption, Eddy Chen and Brett Yang are credited with making classical music accessible
TwoSet's mission to give more people a chance to engage with classical music is a challenge many organisations are facing with falling ticket sales.
Brian Kavanagh, a lecturer in digital innovation at King's College London, says the duo have shown how important it is for acts to engage with social media to welcome a younger and more diverse audience to their performances.
"One of the things that's really impressive about what TwoSet Violin is doing is that they offer a very wide range of content," says Dr Kavanagh, who has worked with non-profit classical performers, including the LA Philharmonic Orchestra and the English National Opera to help them adapt to the digital world.
"I think orchestras and opera companies and string quartets can benefit from offering perhaps a wider range of [online] content and not just content that we expect from these ensembles."
Alongside Eddy Chen and Brett Yang, fans of TwoSet Violin have been inspired by a fictional musician the duo have created, called Ling Ling.
"Ling Ling is a representation of that perfect model student that your mother always compares you to," Eddy Chen explains.
TwoSet's fans actively post on Reddit and share memes encouraging others to practise 40 hours a day – just like Ling Ling.
Traditionally, many in the classical music space have been under pressure to strive for perfection. That's a perception the duo aim to break by encouraging practice and shunning lucrative sponsorship deals that other content creators accept.
TwoSet claim their 2017 tour was the first ever crowdfunded classical world tour. The duo raised almost A$35,000 ($23,000; £18,000) in online pledges by live-streaming a five-day non-stop "busking marathon" on the streets of Sydney.
Even on their second world tour – which began in Hong Kong in June and sees the duo perform in 27 cities including Helsinki and New York – the practice doesn't stop.
"Half the practice is performing it. You can practise all you want in the practice room. But when you're on stage, it's going to be different," he says.
The response of TwoSet fans suggests a growing audience online is waiting to be part of the classical music world.