Yes, that would work. The total current will likely need to be ~100mA minimum (depending on a number of conditions). The electrodes are metal tubing - pure Nickel works very well. The proper name is Nickel200. Nickel plated brass tubing was originally used for the speakers, but the plating must be pinhole free.
That plasma tweeter is so that good that it's simply not there. Music magically appears. 2 problems: Ozone inhalation and thrown-out backs from moving expensive-to-refill He cylinders around. Another problem is that He gas is getting scarcer and scarcer. The stuff is mined, and when the last bit is extracted, no more He on planet Earth. It's not being replenished through any natural or man-made meas.
I worried about the Helium loss until I learned that huge quantities of Helium are being used in rockets as a pressurizer. A few plasma drivers don't even come close. More is wasted on party balloons. It is leaking out of most natural gas wells too. A product of the radioactive decay of Thorium, it ends up in the same pockets where natural gas is trapped.
Forget Ozone; that's a myth. It is destroyed by the hot plasma. I know because I ran the test in a closed room back in 1979.
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The hot plasma makes ozone. That is how ozone is produced commercially, it is called the Corona Discharge method.
Corona discharge is "cold". Ozone is destroyed by heat. The Plasmatronics plasma is a glow discharge and is extremely hot - if you place a quartz rod into the plasma it will glow red hot.
The Ozone test I mentioned was performed by me when Alan Hill rented an Ozone meter. The speaker and meter were placed in a closed room together. The meter was allowed to record the room air before turning on the plasma. The Ozone level seen before turning it on dropped in the room after it was lit.
Nelson Pass was poisoned by ozone because he created a huge (cold) corona discharge speaker.
This information should be sufficient to kill this persistent myth.
Here is a photo of one of my resurrected plasma drivers. The color is not quite right. The cathode areas are a bit more on the rose-lavender side of the spectrum (from the ionized Helium) and the main column is more greeny-yellow (from ionized Nitrogen). The distance from the anode to the center cathode is ~1 inch.
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Thank you for sharing this image and info, very helpfull indeed !
The laminated metal sheets in the back need to have a resistive connection between each other to help the flame jump (like a bridge) at start-up. I was wondering if metal rods can be used instead to help cooling the flame a bit.
Another thought i had was using porous material like graphite instead of nickel tubing. This way the heat will be spread over a larger area (if the plasma is obedient).
The laminated metal sheets in the back need to have a resistive connection between each other to help the flame jump (like a bridge) at start-up. I was wondering if metal rods can be used instead to help cooling the flame a bit.
Another thought i had was using porous material like graphite instead of nickel tubing. This way the heat will be spread over a larger area (if the plasma is obedient).
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The copper sheets are electrically isolated from each other and do not contribute to start up. They are perpendicular to the electric field so as not to interfere electrically while removing heat.
I cannot think why graphite would be better than the nickel tubing.
As a very young fellow I got to hear the Hill speakers at a local audio show in Atlanta sometime in the 1970's.
It was held at the Hyatt hotel.
I had been playing with audio gear since I was 15 but was still very ignorant of what high quality audio was. I am guessing I was 23 years old.
Dr. Hill was a very stately presence in the room. Humble and kind in the extreme.
I learned a very important lesson that day much as you describe - the high frequencies did not call attention to themselves - they were there but none of the sounds we had assumed were just part of the hifi deal - before i got acclimated I thought there were no high frequencies at all - and then I began to understand.
I have always felt very lucky to have heard them even in this rudimentary situation.
I think you must be referring to the Atlanta Hi End show in Spring of 1978(?). That was our second show. Alan insisted on bringing his beautiful Ampex reel to reel in the trailer. The poor thing suffered from all that mileage. He stopped bringing it after the Chicago CES of that year thankfully.
Well, of course, but there was lots more being brought to (unwanted) attention back then.
I do wonder if the Hill tweeter would sound as extraordinary in comparison to what we have today?
I am sure there would be some advantage but not as much.
Now what would be interesting is for someone to make a speaker with a similar leap in quality in 2021.
Not sure if any can match ionic speakers as these have very low mass (ESL's could and maybe a AMT).
The advantage of the Hill was that the ampifier was part of the speaker similar to a direct drive ESL just single ended class A.
The only thing i don't know is how quiet these are as i like to listen at night and do not like any hiss or what so ever from my system.
The standard ionic tweeters are inaudible when in use (i use some Ionovac's at this moment).
The advantage of the Hill was that the ampifier was part of the speaker similar to a direct drive ESL just single ended class A.
The only thing i don't know is how quiet these are as i like to listen at night and do not like any hiss or what so ever from my system.
The standard ionic tweeters are inaudible when in use (i use some Ionovac's at this moment).
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