ESS Heil air motion tweeters- love/hate?

thedelihaus

Nocturnal transmissions
Interesting design tweeter, but as with anything, I find, in same posts on other forums, both a strong love and a deep-rooted dislike for these drivers.

First-most- for those who are not fond of these, can you tell me why? What are the shortcomings? Is there a flaw in the general design? Is there an audible flaw? Are there mechanical and reliability issues? Unrealistic demands on amps?

And fans- what's the attraction? What draws you to the sound? Do you feel it's a superior design? Have they been reliable?


I see that they are being offered/manufactured once again. Parts/rebuild kits exist.

I know that this doesn't always mean the driver/design is superior- but it does illustrate, even if flawed, it's still an admired, desired and to some, worth the effort/expense.

Thanks,

Paul
 
Hmmm....by your post you have really seemd to answer your own question, so I'm not sure what your asking-except for opinions.
Properly implimented, it is a fine driver and one of the few that can render the correct tonal balance and dynamics of piano's for example. It has a way of floating the music not only around the listening area but into other rooms as well with almost the exact same detail and in the listening area.
Probably best implemented in a 3 way design with a transition driver handing off to the Heil to minumize and possible AMT/woofer disconnect. Also really requires quality driving equipment (matching) to sound it's best, not unlike Quads, or Theils Magnepans and the like.
The ESS AMT3's where probably their best model, and when properly refubed and rebuilt, will give most speakers a truen run for their money.
I have 2 pairs and couldn't be happier with their performance. The wall of sound, imaging, and fast enveloping bass and dynamics they produce is hard to find in most speakers IMHO. The sheer musicality is really uncanny.
Sort of Magnepanish with better imagine and tonality and bass, but on a different level. I have a pair of SMG's-which I love-but the main listening is with the AMT3's.
When referring to older ESS Heil and AMT design's, condition of cabinets and crossovers and associated parts have to be taken into account-if they aren't up to snuff-the sound will suffer, like anything else that has malfunctioning parts.
IMHO peole that 'hate' them (seems a strong word) probaly haven't heard a set properly implemented in the speaker design it's self, and driven by compatable equipment.
They take some work to refurb etc, and find the truely compatable equipment to drive them properly (in the case of the AMT3's I'm reffering to) but well worth it IMHO.
But the Hel's, AMT's etc-like anything else in life-you can't please all of the people all of the time.
Hopefully this helps.:thmbsp:
 
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Hmmm....by your post you have really seemd to answer your own question, so I'm not sure what your asking-except for opinions...

Pretty much nailed it. :thmbsp: I find great value in hearing people's opinions. Helps flesh out a nice picture. Kind of like the frosting on a cake of facts.

...Properly implimented, it is a fine driver and one of the few that can render the correct tonal balance and dynamics of piano's for example. It has a way of floating the music not only around the listening area but into other rooms as well with almost the exact same detail and in the listening area...The wall of sound, imaging, and fast enveloping bass and dynamics they produce is hard to find in most speakers IMHO. The sheer musicality is really uncanny.hopefully this helps.:thmbsp:

Great write-up and well worded.

...Probably best implemented in a 3 way design with a transition driver handing off to the Heil to minumize and possible AMT/woofer disconnect...When referring to older ESS Heil and AMT design's, condition of cabinets and crossovers and associated parts have to be taken into account-if they aren't up to snuff-the sound will suffer, like anything else that has malfunctioning parts...

My wildly loose thoughts have been with implementing them in a DIY arrangement, with a smaller woofer, as it'd be a small room, and implementing a subwoofer, if ever placed in a larger room.
 
I love the Heil driver. It did not replace the average dome tweeter for various reasons, one of which was cost.
 
My only listening experience was 35 years ago. A friend had a set of ESS speakers with the Heil AMT. (can't remember which model) The thing I recall is that for me, they were a little too 'hot' sounding. Too much sizzle bordering on harshness. They were fed with very good equipment, no trash.....

I'd be interested to hear a set again to see if they sound any different to my 'older' ears.
 
I disliked the systems they were used in. For all I know they were good tweeters poorly used. Or maybe not.
 
I disliked the systems they were used in. For all I know they were good tweeters poorly used. Or maybe not.

Tom, I've read this from many people. From a disconnect between the tweeter and the rest of the drivers (the other drivers sounding as if they couldn't keep up) to an outright complaint the woofers were poorly controlled, bass muddy and this, in contrast to the fast, agile tweeter.
 
Interesting thread. I was toying around with the idea of gertting a pair to be used with my DIY four way active speaker system, but IDK how well they would integrate with a pair of ALTEC 811B Horns used for the upper midrange.
 
Tom, I've read this from many people. From a disconnect between the tweeter and the rest of the drivers (the other drivers sounding as if they couldn't keep up) to an outright complaint the woofers were poorly controlled, bass muddy and this, in contrast to the fast, agile tweeter.
Yep.

It seemed that the tweeter was too hot but dang that thing was clear.
 
I think its dependent upon equipment.
I have a pair of the AMT1B's and think they sound great once you find the right amplifier to drive them with.
 
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Simply put, I love 'em!

As with ANY driver, you can impair them with a bad implementation --overdriving them or asking them to perform outside their inherent limits, pairing them with inappropriate drivers/crossovers, etc... Most of the criticisms of the original ESS speaker implementations came from 2-ways that had the Heil AMTs going lower than their ideal crossover point (at least for the volume they were producing at those frequencies), and thus creating a bit of a "hole" between them and the woofers. Also, the AMTs are so fast, it is difficult to find conventional drivers that can keep up with them. These criticisms, IMO, are not really valid, because while true, they represent INappropriate applications of the drivers: employ ANY driver in ways that are inappropriate for it, and you'll find cause to complain.

That said, for the ranges that they work well in, the AMTs are among the very best transducers ever made, period. Only a few ribbons, electrostatics and plasma drivers can come close to competing.

Incidentally, the ultimate way to hear what these drivers are capable of, is probably in an open-baffle line array configuration. Line 'em up, and put some absorptive baffling on each side. Get 8 or so pairs lined up (for a typical room height), set them away from the back and side walls, and hear sound like you've never heard before...
 
I think its dependent upon equipment.
I have a pair of the AMT1b's and think they sound great once you find the right amplifier to drive them with.

I have the AMT1b's also and I agree 100%. In the past I had Cornwalls, DQ-10's, Vandersteen and many other fine models, but when I got the ESS speakers the rest were sold off. It's true that the woofer in AMT1b's can't "keep up" with the Heil tweeters- I've heard better bass. But they are still the best sounding speakers I've ever had. Once I got them, I moulded my amp, preamp etc around them, swapping in and out until I got the best sound from them.

I had them paired with AMT10b bookshelf speakers (also with a Heil), and they all sounded great. But the AMT10b's have recently been replaced by Snell K/II's- for some reason, this combo just sounds better.

BTW ESS is still in business and still selling both the Heil tweeters and replacement woofers.

http://www.facebook.com/pages/ESS-Labs-LLC/10150109682755562
 
One further note:

If the Heils are working correctly, you can put your ear a few inches away from them and hear why they are prized. The sound is so distinct (their motto was: "Sound as clear as light") that you can hear every instrument as clearly as if they were playing in the same room. There is none of the brightness or "buzz" of the high end that other tweeters display when heard from a few inches away.

Obviously these are not the only tweeters that do this- but the Heil design ensures that it is consistently clear and natural sounding.
 
Folks need to remember that the Heil was used in ESS speakers of the 70's and early 80's. ESS used some KEF drivers for early speakers (not using Heils IIRC) and then switched to CTS and other fairly off the shelf drivers. Most of the woofers used were, IMO, pretty mediocre in terms of build quality, consistency, power handling, and frequency response. I suspect all ESS woofers couldn't "keep up" with the AMT's used.

Speaker Design was during the introduction and growing use of TS parameters but much of it was trial and error and design choices. I think the use of the passive radiator designs were fairly poor at controlling woofers and getting tight bass. Only KEF at the time had computer aided driver production and grading of their in-house drivers. JBL had tons of experience and upgraded testing and production facilities to work with.

What I'd really like to see is coupling an AMT driver to a well designed and implement JBL woofer whose efficiency more easily matches the AMT.
 
I've got one of smaller ESS speakers, the PS-8's that I still use. They were a small Heil, 8" woofer, and a 10" passive radiator on the back. I always thought these were a very good speaker. The 8" woofer probably has a higher range than the 12" of some of their other speakers, so I never noticed a gap in the response of the speakers that others have noted on the larger models. And they are accurate, as well as loud. I never tire of hearing a crisp horn or piano being played thru them.
 
From a disconnect between the tweeter and the rest of the drivers (the other drivers sounding as if they couldn't keep up) to an outright complaint the woofers were poorly controlled, bass muddy and this, in contrast to the fast, agile tweeter.

That was pretty much my impression. I would be interested to hear a modern implementation with better integration at the crossover and better bass.
 
What would be interesting is if someone took this technology and made a much taller driver. Would that enable it to have a lower crossover point or maybe even be a full range driver?
 
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