Plasma speakers anyone with info?

The name of the speaker was the Hill "Plasmatronic", and it did emit a lot of ozone as a byproduct; very hard on the lungs and other vital tissues. It was a fascinating concept speaker, but quite literally a health hazard.

While i've never heard a Plasma tweeter, i've been told by others that i trust that there are NO other options once you've experienced them first-hand. Their speed is unmatched by any type of driver based on a physical material. In specific, the Hill Plasma drivers were bone flat out to 40 KHz and remained linear out to appr 100 KHz if i remember correctly.

I know that our friend overseas ( the magical and mystical Detlof ) uses Plasma tweeters with E-stats for mids and large planars for bottom end. He's a good guy and would probably be glad to fill you in on specifics such as benefits, drawbacks, safety precautions, etc...

I can dig up a site where a guy had several hybrid dynamic / plasma speakers for sale. Some were still new in the box if i remember correctly. Drop me an email if you're interested and i'll try and hook the two of you up... Sean
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Acapella audio of germany is currently producing three models with horn loaded plasma tweeters (and they've apparently figured out away around the ozone problem). This is your best bet. It may be something like acapella??.de Nelson Pass (of Pass Labs) built one back in the '70's called the Ion Cloud so he may be a source of information. I have seen one or two other units that looked to be current production models: one a japanese company and the other using TAD drivers.

I own a pair of the before mentioned A-Capella Ion speakers and I'm still very much alive.
They have the ozone problem licked a hundred percent and there are no precautions to be taken. I see no drawbacks except the price, which is hideous! (About $ 3500 to 4000 a pair, if you can get them at all, because A-Capella does not sell them singly, but only together with their speakers.) The advantages are a far better sound stage rendering, much more depth and you can listen far deeper into the soundstage. They take careful placing and blending, but which speaker doesn't and to these ears they beat every tweeter I have ever listend to. (Decca & Sequerra ribbons especially, which I know best). You can adjust the frequency, where they set in. Besides they go up so high, that with certain music you have amorous bats clamouring to get inside! (-; You'll get more information through www.acapella.de
Cheers and a merry X-mas to you all!
Detlof

There's a big difference between the Hill Plasma type of
speaker and the "Ionovac/Ionophone" horn loaded style of
"plasma" speaker.

The former used a large gas plasma that was directly
modulated by AF at high voltage.

The latter uses an RF signal to generate a very tiny (and
hot) plasma which is indirectly modulated by AF high
at high voltage.

Both are similar in terms of needing a plasma, but the
latter case must deal with the effects of horn loading,
and limited LF response.

Both have some background hiss from the plasma itself.

The Hill had the single most impressive mids and highs
that I can recall - fantastically coherent and dimensional.
Their bass was less wonderful. The Hill used "Argon"
welding gas to create the plasma, so it "leaked" into
the room (presumably on the floor, as it is heavier than
air), so they are safe with an exhaust route for the remaining
gas to get out of the room.

Neither make excessive amounts of Ozone. There's more ozone in the air in any major city than these are likely to produce in your listening room.

Magnat made a pure plasma tweeter many years ago, it was an
omni from what I understand - never heard one.

I did an on paper design of a wide range omni, direct radiator
plasma driver some years back...I think it would work.

I don't know about the Acappela tweets, anyone got a URL?
Are they horn loaded??

_-_-bear