Media playback is unsupported on your device Media caption Get to know Young Musician finalists Max, Rob and Lauren

The three finalists for BBC Young Musician 2018 are cooler than three cucumbers in a freezer in an igloo during the last ice age.

Two of them have never played with an orchestra before and two of them have major exams next week - but they were all remarkably relaxed when we caught up with them at rehearsals on Thursday.

Perhaps it's because all three - saxophonist Robert Burton, cellist Maxim Calver and pianist Lauren Zhang - have been preparing for this moment for their entire lives.

Maxim left home at the age of eight to study at the Yehudi Menuhin School, while Lauren's family moved from the US so she could attend the Birmingham Junior Conservatoire.

They each battled through their respective categories earlier this year to reach Sunday's grand final, where they'll perform a concerto of their choice, accompanied by the City of Birmingham Symphony Orchestra.

"We decided on the three finalists because they all were just incredibly, intelligently musical," says Kerry Andrew, chair of the judges.

"They just had incredible maturity and assurance."

You can watch performances and learn more about the teenage musicians below. The BBC Young Musician final will be broadcast from 19:00 BST on BBC Four and BBC Radio 3 this Sunday.

MAXIM CALVER - Cello

Media playback is unsupported on your device Media caption Maxim Calver's performance in the BBC Young Musician 2018 strings final

Max Calver was playing string instruments before most of us learn to read or write.

"I honestly cannot remember the exact age I started playing," he says, reckoning that he was "about three and a half" when he first picked up a violin, before falling in love with the cello.

"The highest [notes] are close to the human voice. Then down low it's really bassy and meaty. I feel it's got the perfect balance," he says.

By the time he was eight, Max had been accepted into the Yehudi Menuhin School in Surrey, which meant moving out of his parents' home in Gorleston-on-Sea in Norfolk.

"When I first went to school, it was quite difficult." he recalls. "I saw my parents every weekend. They used to drive up, take me home and drive me back, so it was quite long hours in the car - but it's really made me grow as a musician."

Now 18, he's been balancing rehearsals for the grand final (where he'll play Tchaikovsky's Rococo Variations) with preparations for his A-Levels.

"I have to say there's been more practice than revision," he admits.

LAUREN ZHANG - Piano

Media playback is unsupported on your device Media caption Lauren Zhang's performance in the BBC Young Musician 2018 keyboard final

Lauren has a home advantage. Not only is the Young Musician final taking place in her home town, but she's played at the CBSO Centre before with the Birmingham Junior Conservatoire.

Born in Albuquerque, New Mexico, Lauren applied for the Conservatoire in 2010 while her mother, Hui, was taking a sabbatical year in Birmingham.

Although they planned to return to the US, Lauren's experiences at the school encouraged the family to stay put.

"It's a really warm, supportive environment," says the 16-year-old. "You can tell everyone there really loves what they're doing".

As well as being an accomplished pianist, Lauren also fences and studies violin ("I picked up violin because I needed to do something more social, like joining orchestras," she explains).

On Sunday night, she'll play Prokofiev's Piano Concerto No 2, a piece she chose because it balances "lyrical, elegant" melodies with moments that are more "grotesque or bizarre".

But if she wins, Lauren won't have much time to celebrate - she starts her GCSE exams on Tuesday.

ROB BURTON - Saxophone

Media playback is unsupported on your device Media caption Robert Burton's performance in the BBC Young Musician 2018 woodwind final.

When Rob Burton was told he'd made it through to the final of BBC Young Musician, he clasped his hands to his face in disbelief.

"It just feels so surreal," he says as the big day looms. "It's something I never thought I'd be doing."

In fact, the teenager was so confident he'd be eliminated that he didn't start practising the piece he'll perform on Sunday - Paul Creston's Saxophone Concerto - until his place was secured.

"I chose something thinking I wouldn't have to do it," he admits. "It's constantly on my mind [now], so it'll be lovely to play it."

This year's oldest competitor, the 18-year-old grew up in Cambridgeshire on his family's farm, but was seduced by music early on.

"When I was five I started playing recorder at primary school," he recalls. "As my friends started to drop out of lessons, I was the one who kept going."

He picked up the saxophone when he was nine and now practises for seven or eight hours a day at the Royal Academy of Music.

"I love the saxophone because I just find it so exciting," he says. "It can produce so many different colours. It has such a richness but also beauty and power."

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