Hill Plasmatronics Type 1 loudspeaker Manufacturer's Comment

Manufacturer's Comment

Thank you for a very fine report on the Type 1. Other listeners, too, have commented on the impression of brightness that the system gives with some program material, so we are making available as an optional factory add-on a switch such as JGH proposed. It still bothers me to have to do this, though, for the system is< flat in response according to every measurement one can make, and it seems almost criminal to equip a high-accuracy reproducer with what amounts to a fidelity killer.—Alan Hill PhD

Reviewer's addendum:
Our own experience, through all these years, has been that point-source transducers (such as the Plasmatronics) that measure flat at the high end have invariably sounded tipped-up at the high end. We will be indebted to any reader who can shed light on that little niche of darkness.

Why we can sympathize with Dr. Hill's reluctance to "cripple" the high-fidelity potential of his speaker system—an act that has been colorfully likened to lighting afire and then pissing on it—we do not see how a "fidelity switch" would impair the value of the system as a reference standard for program evaluation. If the user agreed with Dr. Hill that the system is indeed more accurate without the switch, it could always be turned off when one desired for evaluative purposes rather than for enjoyment.—J. Gordon Holt

Plasmatronics, Inc.
Albuquerque, NM 87106 (1979)
Company no longer in existence (2014)

c1ferrari's picture


remlab's picture

A plasma tweeter crossed over at and allegedly flat down to 700hz? Is that a typo? The modern Lansche plasma is crossed over at almost 3 times as high.
Reread the review. It's obviously not a typo. Wow!

bpw's picture

I heard the Hill Type 1 at a couple of shops back in the 70s.

At WCES '92 in the old Sahara Bi-Level a pair of prototype full range (!) cold air plasma speakers were demonstrated by Tolteque AHL of France, but the company went out of business not long afterward. Each speaker was 9' tall by 5' wide.

remlab's picture

I already stated that it wasn't a typo.
If it took 500 watts to get a plasma tweeter down to 700hz, I can't imagine the power it took to go "full range". There must be something on the internet mentioning this speaker. All I can find so far is this..
J.M. Willigens on the Tolteque: Their manufacturer, AHL, a subsidiary of a steel mill in Haut Languedoc (south of France) went out of business around 1995. Their product line included three different Tolt'que models, differing only in height and called "americain", europeen and japonais to reflect the differing ceiling heights required to accommodate them. The Tolt'ques were originally meant to use the "cold plasma" ionization technology, which proved unpracticable, but a lot of the research work, particularly concerning transformers and isolation, was used for an ESL development.

bpw's picture

I wasn't disagreeing with you, merely reiterating.

Somewhere I may still have the brochure on the plasma speaker. They were using a pair of big McIntosh amps, I think 750 watts, which were definitely breaking a sweat (the front panel VU meters were clearly getting way up there) just playing light classical music at modest volume. The people from the company, who spoke almost no English, said something about not having the necessary voltage out of the wall (they were expecting 220V?) to enable the speakers to play louder. They estimated a price of $80k for a pair, assuming they would ever be produced.

You are unlikely to find anything more on the web about the company and products because they are long forgotten.

remlab's picture

Was it horn loaded? I would imagine it would have to be.

bpw's picture

No, it wasn't. The ionization chamber (active driven area of the speaker) was about 4 inches square. I really don't remember much. After all, that was over 22 years ago.

audiolab's picture

Shame... that the world is running out of helium

yaka24's picture

more expensive electronics than in the picture (emotiva) were used it would sound better

remlab's picture

..the high value leader right now. Amazing stuff for the money. Stereophile definitely needs to review some of the electronics in their lineup.

corrective_unconscious's picture

Typed by hand from the manuscript / magazine issue or from a Tandy computer file?

"(An ion is an atom having more than or fewer than its usual complement of electronics.)"

If that is the original text then there should be a "[sic]" put in.

If it's a transcription error than it should be fixed. Same for the word "od" which you can find in the review proper. Maybe others - I've only scanned the first page.

We don't want W.D. going on a rant about how "Stereophile" hates electrons, now do we?

John Atkinson's picture
corrective_unco... wrote:

Typed by hand from the manuscript / magazine issue or from a Tandy computer file?

Ran a scan from the original magazine through a text recognition app, then cleaned it up by hand.

corrective_unco... wrote:

If it's a transcription error [then] it should be fixed. Same for the word "od" which you can find in the review proper.

Both fixed. Thanks for the proof reading.

John Atkinson
Editor, Stereophile

corrective_unconscious's picture


You're messing with my mind again.

remlab's picture

Anality to the point of banality. Ugh!

corrective_unconscious's picture

You should learn what an ellipsis is.

If you merely stutter then I apologize, naturally.

remlab's picture

Thiss iz geting funn!

hexguitar's picture

I was 25 years old in 1979 when I stumbled upon Audiovision in Dallas.

This was my first glimpse of true high end audio.

Audiovision had two large rooms.

The largest contained lower to mid-priced high end gear. There were speakers from DCM (Time Window), Magnapan (MG-I, MG-IIA), Mordaunt Short, etc. Electronics were from NAD and Harmon-Kardon. Sources were from NAD, Eumig, and Denon.

The second room, which was about 20 by 35 by 12 contained the high priced gear. This room had Threshold, JVC Pro (imported directly from Japan), and Beveridge electronics. The Beveridge pre-amp in the main system had two chassis. One chassis had the power supply. The other contained all of the rest of the pre-amps guts.

Speakers in this room included Magnepan Tympanis and Beveridge hybrid electrostats.

Here is where I saw and heard the Hills.

My initial reaction was similar to virtually everyone I subsequently observed hearing (and seeing) Hills for the first time. I was startled.

When first fired up (sorry, I couldn't resist the pun), the plasma emits a small "pop" as it forms. It also visually produces a blue flame between the nozzles that seems to dance in the air.

Then the music started and I was again startled by the clearest, most life-like reproduction of recorded music I'd ever heard. The recording being demoed was a solo A Capella contra-basso male voice.

The image produced could have fooled me into believing the invisible man was singing in the room.

I ended up talking the owner into giving me a job. We sold three pairs of Hills in the 10 months I worked there. In late 1979, the owner announced that he was bleeding money and had to close.

The Hills did have maintenance issues. Guy Oliviera, who was the store manager, did tech work on the store's Hills. They broke down frequently.

But when they functioned, they played better than anything I've ever heard.

Steven Kastner

psteet's picture

When the store went under, Todd, the owner, came back to Austin and stayed with me while he looked for another place. He ended up trading me the speakers for rent and I owned them for another twenty years. Other than the expense and inconvenience of the helium, they were a joy to have and listen to. To this day I have never heard speakers with better high end. I finally sold the tweeters to a man in Canada as he did not want the whole speaker and offered and remarkable amount of money for them. I am happy to have been the owner of one of the most unusual and downright remarkable pieces of audio gear ever produced.

Plasmatony's picture

I worked for Alan Hill all those years ago. I have a pair of plasma drivers and have revived them with new electronics. It is such a joy to have them back in operation. Alan is still alive and kicking and rumor has it that he has plans...

remlab's picture

Pretty freakin crazy! Horrid music on the video. Have your own plasma speaker for $100.00!

Bob Henry's picture

I likewise attended WCES '92 and stumbled upon the Tolteque plasma loudspeakers.

So large they nearly occupied the entire room.

And so wide (each unit 5 feet) that stereo imaging was imperceptible.

As for the Hill Plasmatronics, I first heard them in Los Angeles at Ken Mavrick's Audio One store.

The violet-colored flickering plasma was something to behold. And the sound reproduction was freakishly real given the right source material (e.g., human voice, acoustic instruments played at moderate levels).

Made me covet them over my Harold Beveridge loudspeakers, whose mid-range naturalness and "3-D" imaging was first-rate.

As for other cutting edge loudspeaker designs, I never auditioned John Iverson's Electro Research "force field" loudspeaker. (One WCES display anecdote I heard was that the ozone it produced made listeners nauseous and/or gave them a headache.)