Mythbuster Adam and ArcAttack do Dr.Who

[LadyTevar]

[Agent Fisher]

On so many levels, this is awesome.

[The Grim Squeaker]

For anyone who hasn't seen the original:
[youtube]http://youtu.be/PdrqdW4Miao[/youtube]

They also have an awesome take on the Imperial March

[HMS Sophia]

That is so very cool.
How is it done?

[Broomstick]

Let's see if I can remember how this is done without murdering it - according to the guys out of Fermi lab I talked to (who also do a show) Tesla coil output has a frequency associated with it. Modulating the frequency of the sparks produces a pitch. If you can do it precisely, you can get something like musical tones at standard musical pitch.

I saw something like this live at a DucKon. The guys there call it a "Zeusaphone", after the Greek God Zeus of course.

Oh, and in real life these things are loud. With the smell of fresh ozone. Lots of it.

[Crossroads Inc.]

"Here, come, the DRUMS!!!"

Zeusaphone most awesome instrument ever!

[starslayer]

That is so very cool.
How is it done?

It's basically a giant Plasma speaker. Since the current in the spark heats the air inside it, as you turn up the current, the air expands; turn it down, it cools and contracts. Modulate the current rapidly, and you can generate a tone; carefully controlled, you can actually get extremely clean sound out of one, although the ones in the Wiki article tend to roll off at low frequencies since their arcs just aren't that large.

Tesla coils are convenient for this type of thing because they're already pumped by AC, so you've got a ready-made sinusoidal current source. They also have the advantage that, since they're generally so large, they can do very low frequencies as well and also get loud without even trying. However, they usually draw power from the wall, so that 60 Hz + harmonics buzz comes in just about no matter what you do.

[Eternal_Freedom]

That....is just awesome.

[MrDakka]

A bit off topic, but watching this video made me wonder if you could modulate gravity waves (i'm not even going to pretend to know how), would it be possible to set up a system so that a spaceship hull can act as a speaker?

[MrDakka]

A bit off topic, but watching this video made me wonder if you could modulate gravity waves (i'm not even going to pretend to know how), would it be possible to set up a system so that a spaceship hull can act as a speaker to those inside?

And could this setup be modified to work on planets? You could scare the crap out of some poor astronauts, with no readily apparent speaker... THIS IS THE VOICE OF GOD AND YOU WILL RESPECT MAH AUTHORITAH!

crap sorry for the double post been lagging

[Beowulf]

Please don't necro old topics with off topic replies.