Its name means 'sweet sounding', it looks a little like a tuba, it's regarded as the cello of the brass section, and Byron 'Buzz' Newton is one of the best players of it in the business.
When the young Buzz Newton signed up to play a brass instrument with his local Ashburton band, the euphonium wasn't on his mind.
He wanted to play the cornet.
The bandleader asked Newton to smile and handed him a baritone horn. But Newton's teeth were too big for a cornet mouthpiece.
Talking to RNZ Concert host Bryan Crump, Newton suspects the band may have had ulterior motives.
"I think it was probably more that they needed a baritone player."
The set-back didn't put Newton off music, but the baritone (which is a little like a euphonium, only more cylindrical) wasn't winning him over.
By now he'd moved to Christchurch and wanted to play the French horn.
His new teacher encouraged him to stay on the baritone until one day, "my mouth-piece got stuck".
Newton attempted to remove said mouthpiece with the nearest available blunt instrument: a large book – an encyclopedia.
"I tried to hammer it out and broke the lead pipe."
He'd destroyed the baritone, and was handed a euphonium. The rest is music history.
It wasn't the cornet, but it obviously fit.
Few instruments have a more musical name than the euphonium. The name comes from the classical Greek and means 'sweet sounding', although not many people know what it looks like.
"In New Zealand, generally people don't know what a euphonium is. So when people ask me what I play, I say I play a mini-tuba."
Newton went to study in Wales, and in his final performance exam he did so well his examiners marked him at 100 percent.
Did he think he'd given the perfect performance?
"No," he concedes.
He thinks the beginning and end of his recital performance was pretty good, but he slipped off a little bit in the middle.
Still, ask anyone in the New Zealand brass scene, and they'll tell you he is one of the best players in the country, in fact one of the best euphonium players in the world.
However, there wasn't quite enough work in Europe to keep a euphonium specialist gainfully employed, so Newton and his family returned to Aotearoa, where he's based in Wellington.
"The last three years I've been part musician, part stay-at-home dad."
The musician part involves teaching, performing in the Royal New Zealand Airforce Band, playing a bit of the full-sized tuba with Orchestra Wellington and fostering the next generation of brass players through the organisation he helped to set up: Buzzing Brass.
Basically, Buzzing Brass is the youth academy for Wellington Brass, the city's principal band directed by NZSO trombonist David Bremner.
It's called Buzzing Brass in honour of Newton's nickname (which came about because for a while he worked as a beekeeper) and because of the buzzing sound brass players make when they blow into their mouthpieces.
"That's a polite way of describing it," observed Crump.
But while it might sound like a raspberry when you blow in to it, there's no doubt when it's Buzz Newton playing the euphonium, what comes out lives up to its 'sweet sounding' name.
So when will we get another chance to hear Newton in action?
Well, you could click on the video above.
Or, if you live in the South Island, Newton is touring and performing solos with the Royal New Zealand Airforce Band late this month and early in March, with concerts in Blenheim, Ashburton, Timaru and Christchurch.