Tesla coils are known for producing impressive arcs of electrical lightning, but thanks to Kiwi software engineer Josh Bailey, they can also make music.
He's built a special purpose computerised interface called Chime Red that allows musicians to play the high voltage transformers.
Josh Bailey Photo: supplied
The sounds from the Tesla coil are produced mainly by explosive air heating – dangerous only if you’re directly in contact with it, Bailey says.
In fact, when Bailey takes his coil to events, he has a sign to put near it that reads: ‘Not only will this kill you, it will hurt the entire time you’re dying.’
“The primary mechanism is repeatedly heating the air in these very short percussive bursts. If you do that fast enough you can produce musical notes.
“As the arc is moving around, it’s actually moving the air in the same way that a speaker does.”
It can be quite confusing to see in person, Bailey says.
“For some reason I noticed about half the people, when they come see it for the first time, they’ll instantly see where the sound is coming from…the other half of the people will say ‘oh, where’s the speaker’.”
Bailey thinks people who build Tesla coils are quite strange and that many are obsessed with building one that will produce a big arc or output a lot of power - in order to impress people.
“But there’s another community who would like to produce sound with them and if you look for a lot of Tesla coil music online, it relies very much on the physical theatre of it, kind of just blasting the audience into deafness.”
Bailey wanted something more harmonic.
He has worked with electrical engineer and citizen scientist Greg Leyh on giant Tesla coil projects including at last year's Dark Mofo Festival in Hobart.
Josh Bailey and one of his Tesla coils will be joining 500 musicians for CubaSonic, a mass musical performance that's part of Wellington's CubaDupa festival on the weekend of 28/29 March.
