Heil - oops - Ohm - you guys remember these?

[Schurkey]

Did the guys selling the ionic tweeter "forget" to tell you about the

ozone? I have heard that ionic tweeters aren't available in the

US because of indoor air pollution regulations. The arc produces

ozone, ozone is really helpful at high altitude, but not so good at

ground level.

At any rate, it's not new--I remember hearing about ionic tweeters 25

years ago, and they weren't new then. The company was Hill

Plasmatronics. I think those got around the ozone problem by

connecting to a helium tank. The arc excited the helium instead

of air. No oxygen in the helium so no ozone.

http://www.roger-russell.com/ionovac/ionovac.htm#hillplasmatronics

But you talked funny after listening to them

As a science principle, it goes back to some time in the 1800's.

As an actual for-sale product, you need to go back to at LEAST the

'50's.

http://www.roger-russell.com/ionovac/ionovac.htm#generalhistory

[Marvel]

They are using something in the design, with a catalyst or something to

counteract the ozone generation. I can't remember exactly what it is

they are doing now, but they say you can even sleep in the same room

with it. And you can buy them in the U.S.

[artto]

Marvel, I believe you may confusing "Bob Heil" with "Oskar Heil". Oskar Heil invented the Heil Air Motion Transformer treble reproducer (used by ESS) (and a new version in his own current speakers), had nothing to do with those horn loaded speakers John Entwhistle is seen using in that Who photo.

[Marvel]

artto,

Not really confused. Mostly playin' with Dana over this. Bob Heil is

mostly into making microphones these days. A church I belonged to in

the late '70s had a power amp that was a Heil (same logo as Bob Heil's

company). It was so noisy with the fans that we had it mounted in

another room.

But... I'm glad you knew the difference too! [6]

Bruce

[78Khorn]

This flagship of the ESS AMT line offers superb performance throughout the full audio range. Utilizing the unparalleled Heil air-motion transformer in a bi-radiating configuration, it provides unmatched imaging, definition, and detail throughout the critical mid-range and high frequencies. Superior bass performance is achieved through the use of our 12-inch cast woofer in a large volume cabinet, coupled with a front facing bass radiator. The classic styling and acoustic performance make this the natural choice for those who desire the best.