Reading old threads, found some gems. It's looking like plasma will be a game changer.
Found Ulrich Haumann's site: www.plasmaspeaker.de
(Awesome guy) about many different plasma drivers, the he even makes parts.
hillplasmatronics.com Knocked my socks of at warp speed.
I've been studying the schematic and the patent and I'm excited. I'd be willing to go to a lot of trouble to get around inertia.
Hill did all the work, understood the math, (after some hours rereading the patent I don't). A horizontal output tube (6MJ6) regulates the overall current and audio is applied to the grid. 5 units in all, drawing about 1000 watts total. A high voltage PS flows through the discharge to the plate. simple and brilliant.
I plan to make a single unit. One tube, leaving the monitoring circuit out for the moment. I'll start with plain air, then see about renting a pony tank of helium. Balloon helium is out, since it contains some oxygen. (So kids don't fall out breathing it) Not sure if the Hill speakers preheat the helium, but in the patent he says doing so creates a sheath around the discharge, "which results in a spreading and stabilization of the plasma over a larger volume by lowering the density in it's outer regions".
If I can get it to work, I'll make more units.
Found Ulrich Haumann's site: www.plasmaspeaker.de
(Awesome guy) about many different plasma drivers, the he even makes parts.
hillplasmatronics.com Knocked my socks of at warp speed.
I've been studying the schematic and the patent and I'm excited. I'd be willing to go to a lot of trouble to get around inertia.
Hill did all the work, understood the math, (after some hours rereading the patent I don't). A horizontal output tube (6MJ6) regulates the overall current and audio is applied to the grid. 5 units in all, drawing about 1000 watts total. A high voltage PS flows through the discharge to the plate. simple and brilliant.
I plan to make a single unit. One tube, leaving the monitoring circuit out for the moment. I'll start with plain air, then see about renting a pony tank of helium. Balloon helium is out, since it contains some oxygen. (So kids don't fall out breathing it) Not sure if the Hill speakers preheat the helium, but in the patent he says doing so creates a sheath around the discharge, "which results in a spreading and stabilization of the plasma over a larger volume by lowering the density in it's outer regions".
If I can get it to work, I'll make more units.
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Uh, bad idea. The reason why they became unpopular is the high level of ions they produced in the room. This was noted at first by loudspeakers like Acoustats failing as the plastic film diaphragm failed.
So the loudspeakers you make should be safe to use as long as you don't breathe the same air.
Ionizers were popular in the 30's and faded from view as the fresh ozone smell they produced turned out not to be a good idea. They came back in the 70s and went away again.
However the Hill plasmatronic loudspeakers had marvelous high frequency response.
So the loudspeakers you make should be safe to use as long as you don't breathe the same air.
Ionizers were popular in the 30's and faded from view as the fresh ozone smell they produced turned out not to be a good idea. They came back in the 70s and went away again.
However the Hill plasmatronic loudspeakers had marvelous high frequency response.
With a continuous helium feed, ozone is no issue. Ions can be neutralized. I'm ok with providing ventilation. Running at 4000 volts, my ESLs probably made some ions.
I will respect your warning, and forge ahead. That the hill's had marvelous high end response is an understatement. Transient response is the big draw for me. At least as I lay dying from some incurable respiratory disease I'll have great music to listen to.
Link below includes Nelson Pass describing his ozone sensitization after working extensively with a large ion speaker. The whole interview is pretty interesting, as it gets into the limitations of their speaker and some Krell and Dayton Wright history as well.
Nelson Pass’ ‘perfect’ massless, full-range Ion Cloud speaker #audiophile #highendaudio - YouTube
Nelson Pass’ ‘perfect’ massless, full-range Ion Cloud speaker #audiophile #highendaudio - YouTube
You have to be alive and kicking to be able to learn....
So please be warned of all the hazards involved here.
Ozon is very agressive stuff and will react with almost everything including your lungs.
In hornloaded speakers this could be dealt with by adding a creamic tube that neutralized the ozon. However this needed to be cleaned every now and then as the reaction caused sediments.
Plasmatweeter
So please be warned of all the hazards involved here.
Ozon is very agressive stuff and will react with almost everything including your lungs.
In hornloaded speakers this could be dealt with by adding a creamic tube that neutralized the ozon. However this needed to be cleaned every now and then as the reaction caused sediments.
Plasmatweeter
I looked at the schematic and found that this could be a perfect job for a PL81/PL36/PL504 and naturally the PL519!
The voltage used is about 3KV ? I think i have a transformer that can create this easy so maybe i could also try it one day. As my house is now full of stuff i can not start bringing helium bottles home (my wife will not approve).
I think this system can be made more efficient if we will not use a DC HV source but an AC one instead (250Khz or more). Even PP is possible this way. I have to study it more....
Fun project ! Just stay safe !
The voltage used is about 3KV ? I think i have a transformer that can create this easy so maybe i could also try it one day. As my house is now full of stuff i can not start bringing helium bottles home (my wife will not approve).
I think this system can be made more efficient if we will not use a DC HV source but an AC one instead (250Khz or more). Even PP is possible this way. I have to study it more....
Fun project ! Just stay safe !
I can remember the night I first heard an Ionovac.....
But I think ozone will destroy your lungs at concentrations you can't smell. Anybody agree with that fact? Not good, no matter how arrogant you are about your smelling skills and helium protection.
Isn't there any kind of feasible ozone alarm? Anything faster than an annual lung X-ray?
I don't think ions per se are bad. Just ozone. Anybody agree?
B.
But I think ozone will destroy your lungs at concentrations you can't smell. Anybody agree with that fact? Not good, no matter how arrogant you are about your smelling skills and helium protection.
Isn't there any kind of feasible ozone alarm? Anything faster than an annual lung X-ray?
I don't think ions per se are bad. Just ozone. Anybody agree?
B.
Here is what wiki has to say about ozone:
"There is a great deal of evidence to show that ground-level ozone can harm lung function and irritate the respiratory system.[44][89] Exposure to ozone (and the pollutants that produce it) is linked to premature death, asthma, bronchitis, heart attack, and other cardiopulmonary problems.[90][91]
Long-term exposure to ozone has been shown to increase risk of death from respiratory illness. A study of 450,000 people living in United States cities saw a significant correlation between ozone levels and respiratory illness over the 18-year follow-up period. The study revealed that people living in cities with high ozone levels, such as Houston or Los Angeles, had an over 30% increased risk of dying from lung disease."
Over all a bad idea to put an ozone producing device in your house and of course these days almost all audio will have been at some point digitized making the whole exercise not only dangerous but also pointless.
The point of using them with those rare non-digitized sources is debatable unless you want to produce hiss with great accuracy.
"There is a great deal of evidence to show that ground-level ozone can harm lung function and irritate the respiratory system.[44][89] Exposure to ozone (and the pollutants that produce it) is linked to premature death, asthma, bronchitis, heart attack, and other cardiopulmonary problems.[90][91]
Long-term exposure to ozone has been shown to increase risk of death from respiratory illness. A study of 450,000 people living in United States cities saw a significant correlation between ozone levels and respiratory illness over the 18-year follow-up period. The study revealed that people living in cities with high ozone levels, such as Houston or Los Angeles, had an over 30% increased risk of dying from lung disease."
Over all a bad idea to put an ozone producing device in your house and of course these days almost all audio will have been at some point digitized making the whole exercise not only dangerous but also pointless.
The point of using them with those rare non-digitized sources is debatable unless you want to produce hiss with great accuracy.
• Ozone Half Life
o Gas Phase ~ 20 minutes (20° C)
o Residual (Dissolved Ozone) - Decay
o at pH 6.0 ~ 20 minutes
o at pH 7.0 ~ 15 minutes
o at pH 8.0 ~ 5 minutes
o Will vary with reaction rate
Ozone Library
o Gas Phase ~ 20 minutes (20° C)
o Residual (Dissolved Ozone) - Decay
o at pH 6.0 ~ 20 minutes
o at pH 7.0 ~ 15 minutes
o at pH 8.0 ~ 5 minutes
o Will vary with reaction rate
Ozone Library
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Great video! That speaker was very efficient! At producing ozone. Fascinating interview. Now I have to watch all the Pass videos.
A typical "me" result -
I once owned a home in Massachusetts with an in ground swimming pool. Sucker would go green too often and 5 gal chlorine shocks got expensive...
At the town dump, I found this "Ozone generator" - a speaker cab sized metal box full of glass tubes, with little spikey metal points surrounding each one. I hooked up a neon sign transformer to it and a 12V air pump intended for inflating tires. The stinky output I fed directly into the pool side water output, making a nice stream of Ozone bubbles into the pool...
After running the arrangement for days - until the paint on the air pump motor housing turned brown from continuous operation - the green still stood up in defiance. Didint do a damn. All the rubber seals in the pump house plumbing took a good beating however.
Like Wile E Coyote, back to the dump it all went. At least the sound of breaking glass was satisfying.
I once owned a home in Massachusetts with an in ground swimming pool. Sucker would go green too often and 5 gal chlorine shocks got expensive...
At the town dump, I found this "Ozone generator" - a speaker cab sized metal box full of glass tubes, with little spikey metal points surrounding each one. I hooked up a neon sign transformer to it and a 12V air pump intended for inflating tires. The stinky output I fed directly into the pool side water output, making a nice stream of Ozone bubbles into the pool...
After running the arrangement for days - until the paint on the air pump motor housing turned brown from continuous operation - the green still stood up in defiance. Didint do a damn. All the rubber seals in the pump house plumbing took a good beating however.
Like Wile E Coyote, back to the dump it all went. At least the sound of breaking glass was satisfying.
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Yes it is. Ozone is a molecule of oxygen with 3 atoms, instead of the normal 2. For oxygen to react, the bond between the 2 has to break so extra energy is needed to cause a reaction. A single free atom is ready to go and is more reactive. In electrolysis, single atoms form when oxygen ions become atoms. Gold will slowly dissolve as an anode, yet will not combine with normal oxygen. Ozone is unstable. Left to itself, the third atom breaks away, joining up with others, until all the ozone becomes regular oxygen. It's those single atoms that create the hazard.
Ventilation is key, and there is no reason the speaker could not be isolated with a thin sheet of plastic. Positive helium pressure in the cell, an air inlet behind the "tent" with an active draw of air exhausted to the outside.
Awesome that folks here are concerned with health issues. Thanks for the input.
There's no voltage shown on the supply, but the caps are 4k, and if you figure 50 milliamps each tube, the numbers work out for about 3000 or a little more. WAF is our most respected spec, but they do sell helium in small bottles
I've been staring at the schematic for a few days, it's a beautiful thing.Attachments
I wouldn't rely on my nose. Like a procedure in a chemical lab, everything is thought through, including failure modes of protective equipment. I expect there likely is a device for detecting and measuring ozone concentration.
I propose isolating the cell from the air in the room, let the sound through a membrane.
Not sure if it's what you were already thinking, but if you really want to isolate the speaker environment from room air, setting things up so the speaker enclosure has slightly negative pressure may be better. Keeps things flowing the right direction in case of leaks. A liquid manometer could be added as well.
Digital media have little or no effect on transient or frequency response of speakers.
If I do run an analog source, I would certainly insist on reproducing the noise accurately
Probably a hard thing to do. Helium is the smallest molecule and leaks very easily. In fact for high vacuum systems (used in SEMs, sputtering and cryo systems etc.) it is the ultimate leak detection medium when used in conjunction with a helium leak detector.
Keeping the device fed from a tank could get pricey.