plasma speaker

Never heard one myself. Try the DIY & speakers forums. You'll probably get more hits in there.

It looks so darn interesting. I wonder whether it has more fidelity or more distortion compared to high-end speakers, and whehter it can replace a sub-woofer as well. I don't suppose it'd cost a lot to make.

http://www.youtube.com/watch?v=cEeWtBAE5LY#t=0m35s

 

DIY, no less! I don't know if there's a practical way to make one that isn't a tweeter, but it sure is nifty.

So it can only act as a tweeter. And I read it requires some sort of gas like helium to run.

 

I remember this sort of plasma sound has been featured in the film The Sorcerer's Apprentice.

Edited by kingpage - 1/6/11 at 8:26pm

I built a plasma speaker recently with a flyback transformer, no gas or anything. It does produce a little ozone but a lot less than my air purifier does! When the arc is stable it is hands down, the best tweeter I have ever heard in my entire life! It also has 360 degree sound so you can put it in the middle of the room and the sound will be the exact same wherever you are. The volume depends on how many volts you put through the flyback so 12v dc is pretty quiet but I put 19 through mine before the MOSFET got too hot and I could hear it from upstairs. I ordered better MOSFETS so I can put at least 40v through the transformer. Yes, you can make a fullrange, 'perfect', speaker with a plasma arc but the arc would have to be over a foot in length to vibrate the air enough to produce anything lower than 100hz. That probably would produce a lot of ozone and take up a lot of power. Helium gas is used to negate ozone; it doesn't make the arc any better. It would be much easier just to add a subwoofer and midrange speaker to the final design, I'm looking to make a 2.1 system like this, I will let you know how it turns out.

Hope this helps!

Edited by Camp Badger - 4/10/11 at 12:50pm

Oh wow that's incredible!! Would you get electrocuted if your hand went in-between that current? Wonder if it'll pose a fire hazard.. I'd be interested in making a woofer like this! Does that mean the arc has to be really long for it to be a decent woofer?

Plasma drivers are the ultimate - a massless driver. But the ozone is a worry and you'd need some damned serious power to get one down into the mids.

Which reminds me, Nelson Pass created a full-range plasma speaker. It also put him in the hospital. (http://www.diyaudio.com/forums/pass-labs/1841-pass-plasma-speaker-history.html)

Practically speaking, I find ribbons and AMTs easy to live with. They might not be as transparent as plasma, but they're very safe.

Very very interesting for tweeeterappliances, the lower you go the more ozon if I understand correctly. 

But aside from other cons, won't the electrodes burn through or get oxidised very quickly?

The link mentions 6 hours stable; for a tweeter to be usuable it should have a lifespan of at least say 10.000 hours, or the electrodes should be userreplacable easily and cost effective and even then, a few hunderd hours should be the minimum liofespan for the electrodes.

Dura, yes, the electrodes decay quickly. Same problem they had with early electric arc lighting, like the Yablochkov Candle and Brush lighting. They actually had electric public lighting in factories and a few public places. Film studios used them, too. The bulbs burned out quickly and also threw off a lot of UV. A very interesting book about the early history of lighting is "Dark Light," by Linda Simon. Highly recommended if you like this sort of thing. There's a much bigger backstory to electric lighting than Edison and his bulb.

As an aside, my favorite is how some houses were both plumbed for gas lighting and wired for electricity. You can find old light fixtures that incorporate both gas and electric, too. There was controversy over whether it was safe to have electric currents in the house - many thought that gas was safer. One of my low-priority fantasies is to restore an old gas/electric fixture and use it with gas in a dining room. I'm not sure how a building inspector would feel about that, though.

Anyway, as excited as I was initially about plasma speakers, I just don't think they're practical. If an audio hero like Pass ran into trouble with them and they constantly need their electrodes replaced, they'd probably end up in boxes.

Also, I imagine you'd have some trouble integrating them with other drivers. Nothing else could possibly sound as good.