I have to disagree with the previous reviewers rating of the ESS AMT 1B.
The AMT Heil Air Motion Tweeters have no such 7 or 8 decibel peak around 7500 hz. I have a spectrum analyzer and have never measured nothing like this. In fact the Heil because of it's characteristic ability to handle a broad range of high frequencies has not mid-range driver, the Heil handles both mids and highs with aplomb. When placed in the listening room correctly the Heil demonstrates an above average ability to display a flat and accurate frequency response. However they Heil tweeter is designed to project front and back. Depending on what surface the reviewer has behind the speaker this can change the characteristic of the high end frequencies significantly. However a 7 or 8 dB increase is ridiculous and I doubt he measured such a peak. I have measured and used many speakers in the last thirty years and the Heil is one of the best imaging, best phase coherent speakers I have ever heard. In my opinion there is no better device for imaging out there. If the previous reviewer wishes to sell his AMT1 B he will find a buyer very fast.
Comparing the AMT 1B to the Dahlquist DQ-10 is like comparing a jet engine with a prop plane. The Dahlquist DQ-10 is a five way speaker using four regular speakers and one piezo-electric super tweeter. A mishmash of components that was designed in 1974 as compared to a two way speaker with significantly less cross over distortion characteristics and a 360 degree sound field with radical and forward thinking design that was well ahead of it's time.
My two cents, but I think judging by the enormous weight of positive reviews out there this speaker is fabulous. I only wish the original Company is still in business. But I hear that now the patent is with ESS Laboratories so hopefully we will see some more of these amazingly designed speakers out there!

Counter to what others have said, I'd have to rate these less enthusiastically. It has been documented in multiple tests that there is a 5 to 6 db. peak in the frequency response centered at around 7500 Hz. This peak combined with a discontinuity between the lower mid range, and the Heil crossover region, beguiles many into thinking they are hearing superior clarity to other designs. in fact, what you're hearing are the peaks and valleys in their response which happens to accentuate the higher frequency detail, at the cost of tonal accuracy. When actively equalized to tame these response irregularity's, they sound more or less like every other mid-level speaker out there. An ear opening comparison if you get the chance is to listen to a competing design from that era, the famed Dahlquist DQ-10. Side by side, with good musical material; certainly not Rap, heavy metal, etc.
The Dahlquist's, while no longer at the top of the audio ladder, will none the less be clearly superior. Even more detail, but at every frequency from the mid-bass on up. The highs especially will be faster, and have greater extension. More importantly, the sound stage and imaging will be vastly superior, with depth and side to side instrument/vocal placement that the ESS speakers can't even begin to match.
The AMT's do have some advantages:: i.e. much higher efficiency, easier load for an amplifier to drive, and capable of ear bleeding output levels, but then do some old Altecs, JBL's, and even Pioneers.
A side note BTW - replacing the woofers with car sub woofers is insane.That would only compound the problems observed with the stock woofers. The Morels mentioned in another review seem sensible, but a cheap solution is to modify the stock woofers, i.e. eliminate the felt dust cover, and make a wooden phase plug to minimize a cavity response problem, and a coat of modge podge or similar to damp the cone resonances, probably a by a few DB.. Just a suggestion. There's really nothing wrong with a good old paper composite cone if it's shortcomings are addressed. Neo, and Alnico magnets though really help reduce THD caused by magnet eddy currents from bass excursions, which unfortunately these woofers don't have. Still, the mods will help, especially if you use a sub woofer with an active crossover to the ESS AMT-1's, a,b,c,d, etc..

So, if you like strictly electronic music, are not big on imaging, and really like snap, crackle, sizzle, and pop, then you'll be happy as a clam with these. If you have a more refined musical pallet, then you'll be annoyed with the fatiguing sound after the initial thrill has faded.

Amplifiers - Krell and Conrad Johnson Preamp - Audio Research formats- . SACD, and vinyl - classic Thorens TD125 MKll with SME arm.

Favorite speakers - Apogee Diva with Dax....WOW!!

favorite movie this year - Avatar, although hurt locker really was a better movie.

favorite food - hey, I'm Italian so take a wild guess....

I heard these when they were first introduced and always wanted a pair. Since they were outside my price range I held off. Three years ago I got a pair of used ones. The top frame was broken, but some friends of mine took the pieces and built new ones which I covered in speaker cloth.

The sound is so clear. Bass drums are thuds but have resonant presence. The top is natural and never shallow. My older speakers were okay, but I got tired of listening to them. There is no "Speaker fatigue" now. They can handle reasonable volume and make my classical music sound incredible. Country music is clean, too, with the shifts on the strings just being audible. What a pity they don't make them now. I love these speakers and will keep them until someone convinces me a newer system is better. That will take a lot of convincing!

I bought a pair of AMT-1B speakers in 1979. They were moved to different houses etc, several times. A few times I had to replaced the speaker cone and passive radiators because my kids (now in their thirties) and a baby sitter killed them with rap musing and my high horsepower receiver. After ther wooden supporting fram etc. were seriously damaged I finally let them go then later recognized my mistake.

I saw an acronym ESS on my job and was reminded so googled the AMT-1B finding these reviews. It is amazing that they are spoken of now. My current speakers are bookshelf size Klipsch with a Polk subwoofer. Both the Klipsch and the ESS speakers have very clean mid and high tones such that tapping or brushing a symbol sounds like a musical instrument instead of mush. And yes the movie Top Gun made the house move a bit when the AMT-1B's were cranked up. I would be very interested in a pair of the replacements? Do such things exit?

I bought these speakers in the mid 70's and used them for about 35 years. I was able to contact the ESS company several years ago because the rubber mounting around the cones had deteriorated badly but still amazingly sounded pretty good. They sent me newly rebuilt ones in exchange and they played as flawlessly as before. I replaced them a few years ago with a different tower type speaker and gave the AMT's to my son who is amazed at the quality of sound from these "antiques". The Heil air motion transformer was ahead of its time and still an unsurpassed technology. One of the best purchases I have ever made.

Over the many years in IT and while in college in the late 70's and early 80's I have never quite heard a greater speaker with power and clarity as with the ESS AMT 1B's.... Still to this day, no other speaker; in my opinion would sound so good that It sounded down the street like a live band in the garage. It is still the best...

Curtis Sanders in Pasadena

Very efficient
(and with a good receiver:)
Unbelievable bass
Excellent Highs
No distortion even at max volume
Look kinda cool with the Heil transformer on top of them.

Considering these are almost 30 years old its impressive how well theyve held up.

anyone wanting top quality without paying a huge amount of money should defanitly look into these speakers.

Didn't like the covers that came with it so i just trashed them.

I got these speakers from a friend of my dad's who had, had them sitting in storage for quite some time. at the time I didn't know anything about them except they had huge 12" woofers with some weird thing on top of them. Since then I have researched them (mostly from other reviews on here) and realized what they were worth and what the weird thing on top is (a very interestingly desinged tweeter)
There are 2 speakers- the 12" woofer and the tweeter on top- the base is empty and filled with a padding to help with the bass most likely. However you can't remove the top portion of the speaker to make it smaller and lighter (these things are very heavy). Reason I stated this is because I contemplated removing the top portion to save space but decided against it because of way its built to basically be one solid piece. I'm guessing these were made in the late 70's- probably about 1979 because of the other reviews on hear plus the very 70 style grill to go around them (kind of a wood mesh instead of cloth like modern speakers have)
Some people say the most important thing for these speakers is placement, i think its the receiver. when i first had these i had a low quality receiver and they sounded pretty bad and i couldnt believe people were saying these were some of the best sounding speakers they ever had, but then I got a newer receiver and man they sounded 100 times better. I played "Bass Test" to see how good they were and they literally vibrated my skin which is more than any subwoofer has managed to do. An odd property of these speakers I would like to point out is that they seem to sound best if placed on one wall and then wherever you want to listen to them is in the corner because the Bass just really seems to collect in the corners of the room where as if u stand about 5ft in front of them the bass really disapears.
Just as a side note i don't listen to rap and only care about bass but I do like a nice kick&rumble from speakers.
The highs are excellent and very clear as everyone has said.
They are also VERY efficient. the first reciever i had plugged into these only had an output of 15 watts RMS per channel and they were PLENTY loud, just lacked the expected quality. Now the reiver I have qreatly increased the quality as mentioned above.
Also absolutely no distortion with bass,treble, or the midranges. the amplifier in my receiver gets overdriven but up to that point absolutly no distortion (of course this is not the speakers fault so when i go to buy a new receiver this will be fixed)

If you are looking for speakers for any genre of music and want amazing bass and treble then these are defanitly worth checking out.

My dad has Klipsch Cornwalls (the ones with the 15" subs) and these defanitly give them a run for the money sound quality wise- the Klipsch's are defanitly more effiecient though but thats because they are like the top brand and quality so what do you exepect?

Similar Products Used:

Klipsch Cornwall, Boss mulitmedia speakers, Genius, a few other off brands.

Very clear sound, great sensibility, efficiency: just a few watts required for a midium size ambient.

Big. heavy and the lowest bass should be better considering their size, but it much depends on the positioning.

I've been owning a pair of AMT 1B since 1980 and I am of the opinion it has been one of my best choices. These speakers are not the perfect one, but every time I compare them to others even very expensive, I decide to keep on listening to them. Maybe a lack of mids, but it much depends on the positioning in your room. I used a few simple tricks to improve them without changing their philosophy:
reinforcement of the internal cabinet, better connectors, bitumen-paint inside the inner walls, modified PR, insulation of the woofer magnets by using felt cloth. Just a few simple unexpensive activity which helped much in order to clear up the bass., no miracles! Of course I has to re-foam the woofers a few jears ago.
Greetings from Italy!...

Customer Service

Quite good here in Italy, however spare parts to re-foam the passive radiators are impossible to be found.

Similar Products Used:

3 way aperiodic self built speakers sistem. Couple of Canton pls subwoofer.

Highs are crystal clear, power is awesome

Heavy and bulky

These are the speakers of the late 70's. Bose was on the market and Warfendale's, Klipsch but these AMT 1b monitors were just outstanding. I was really into the highs and with the Heil Air Motion Transformers you could really get the highs. Best speakers I ever owned and believe it or not they are in stroage. A few years ago I contacked ESS and they sent me all new covering and connecters and they are still in the package they came in.

Customer Service

Has been outstanding

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