I've never run AMT tweeters, but I've read some positive reviews. It seems like they might excel in reproducing 16k-20k+.
But if that's true, I wonder why they're not more popular. These are the ones I'm considering.
At any rate, do you have any experience with AMT tweeters? Any positives/negatives? Would you recommend them? Anything to know before going down that road?
Any advice or experience would be appreciated. Thanks!
But if that's true, I wonder why they're not more popular. These are the ones I'm considering.
At any rate, do you have any experience with AMT tweeters? Any positives/negatives? Would you recommend them? Anything to know before going down that road?
Any advice or experience would be appreciated. Thanks!
Installed those in a small Toyota coupe, fastened with screws to the door panel next to a new 4" mid. Had to use a test mic and software to adjust crossover and volume, but the young man who bought the car got the flattest response and best imaging he ever heard.
Positives:
In the 1970s the ESS Heil large AMT was far away faster and louder than anything but a horn. But every decade since then, tweeters have gotten better, and better, and better. I built one based on the Neil Davis AMT . It's in my center-channel, and I fiddle with it more than my mains. Check out the exotics speaker section here. If you go down that road, beware of the AMT rabbit hole!
Negatives:
Diffraction response irregularities - you wouldn't put a dome tweeter in a rectangular hole with iron bars across the front, would you?
Beaming on one axis which has made it hard for me to blend it with the mids on that center speaker. I'm running Bohlender Graebener Neo8-PDR planar transducers as sort of helpers on either side of the AMT, small woofers in back.
A 5db plateau between 4 to 8 kHz, again on the big AMTs. Way back in the 70s the ESS Rock Monitor would crash those cymbals like nothing else. Mine has that, and I've fixed it in the crossover, more or less.
So, cars, great. For my listening room left and right, I run modern S&B beryllium tweeters, and they're just so much more musical than the AMT.
Positives:
In the 1970s the ESS Heil large AMT was far away faster and louder than anything but a horn. But every decade since then, tweeters have gotten better, and better, and better. I built one based on the Neil Davis AMT . It's in my center-channel, and I fiddle with it more than my mains. Check out the exotics speaker section here. If you go down that road, beware of the AMT rabbit hole!
Negatives:
Diffraction response irregularities - you wouldn't put a dome tweeter in a rectangular hole with iron bars across the front, would you?
Beaming on one axis which has made it hard for me to blend it with the mids on that center speaker. I'm running Bohlender Graebener Neo8-PDR planar transducers as sort of helpers on either side of the AMT, small woofers in back.
A 5db plateau between 4 to 8 kHz, again on the big AMTs. Way back in the 70s the ESS Rock Monitor would crash those cymbals like nothing else. Mine has that, and I've fixed it in the crossover, more or less.
So, cars, great. For my listening room left and right, I run modern S&B beryllium tweeters, and they're just so much more musical than the AMT.
I'm a lifelong live-music lover and possibly purist audiophile. I only started speaker diy during the pandemic -- working on something new nearly every month. My first diy, for the office-turned-into-temporary-apartment, was a 7-liter tapered transmission line specifically to address my dissatisfaction with a new-old pair of Monitor Audio Studio10 (probably cost a couple thou' thirty years ago) which needed a pair of subs. My 7L was patterned after Eve Audio SC-205 DAC-DSP-active-monitor, in fact used (supposedly) the same make 5.25" fiberglass honeycomb and bigger AMT (1x2" unbranded), 1st-order-series XO and tapered TL in lieu of electronics. I never got an Eve to compare but I figured I had the overwhelming advantage: Chord Hugo, Bel Canto S300i or EL84 SE with Mazda chrome-plate 12AX7; even the AU24 wires cost more than the Eve. The result?
I felt all my listening to recorded music over the years, had been a waste of time. Now I had to play them all again but as new live performances, where each musician improvisation'ed with passion, back-and-forth as part of a lively musical conversation.
A comp might be with one of the last RKO in NYC where I went to see Barbra Streisand's Yentl -- sense of projection. I assume vintage Altec etc. had that and more; way before my time though. My speakers back in the States couldn't compete with the 7L combination of exotic material/technology and very-old-school speaker design. (ESL63; Mo Studios; Lowthers; only the Axiom 80 excepted.)
Since named HeilEve.
I felt all my listening to recorded music over the years, had been a waste of time. Now I had to play them all again but as new live performances, where each musician improvisation'ed with passion, back-and-forth as part of a lively musical conversation.
A comp might be with one of the last RKO in NYC where I went to see Barbra Streisand's Yentl -- sense of projection. I assume vintage Altec etc. had that and more; way before my time though. My speakers back in the States couldn't compete with the 7L combination of exotic material/technology and very-old-school speaker design. (ESL63; Mo Studios; Lowthers; only the Axiom 80 excepted.)
Since named HeilEve.
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Paulfx and wchang,
Thanks so much for your thoughtful replies. You all are on a whole other level ABOVE me!
I'm considering some cheap AMTs for a car-audio build. I posted this question in another forum (specifically or car audio), and it wasn't long before people were talking about those ESS Heils. There's also a German company (Mundorf) that makes them.
I really enjoyed hearing about your experiences. I've been in the hobby for about 20 years--superficially. I find myself obsessively going down rabbit holes to learn more, though, so I can't help but wonder if I'll be at your level in another 30 years! lol
Thanks so much for your thoughtful replies. You all are on a whole other level ABOVE me!
I'm considering some cheap AMTs for a car-audio build. I posted this question in another forum (specifically or car audio), and it wasn't long before people were talking about those ESS Heils. There's also a German company (Mundorf) that makes them.
I really enjoyed hearing about your experiences. I've been in the hobby for about 20 years--superficially. I find myself obsessively going down rabbit holes to learn more, though, so I can't help but wonder if I'll be at your level in another 30 years! lol
I am currently using the Dayton Audio AMT Mini-8 mounted in the pillars of my truck along with the Dayton Audio DMA80-4 in the dash location and have been for a little over a year now. I am using a single cap and coil between them centered at about 5.5KHz.
Like mentioned above, my measurements showed the pair to be surprisingly flat and very minimal EQ adjustments were required above 500Hz and practically none in the range the AMT is playing at. Right now, this pairing is my favorite part of my system. I am chasing better low and mid bass to match it.
Positives for me are, where I have them mounted, not a lot of power is needed to enjoy them at fairly loud levels which is good in that they don't handle much. They will let you know they are too loud with distortion, but fortunately, I have not killed them yet. In my opinion they are not terribly expensive. The AMT / mid combo I have now cost less than 50% of a pair of dash speakers they replaced and are much better.
Negatives, well I'm not really sure just how durable they are in the automotive environment, hot cabin in the summer, cold in the winter, and dirty air compared to using them in the home. Mine are getting direct sunlight through the windshield and I have been expecting to see changes in the Kapton film, but none so far.
I'd say give them a try, but I would also recommend careful selection of the mid you use with it too.
Like mentioned above, my measurements showed the pair to be surprisingly flat and very minimal EQ adjustments were required above 500Hz and practically none in the range the AMT is playing at. Right now, this pairing is my favorite part of my system. I am chasing better low and mid bass to match it.
Positives for me are, where I have them mounted, not a lot of power is needed to enjoy them at fairly loud levels which is good in that they don't handle much. They will let you know they are too loud with distortion, but fortunately, I have not killed them yet. In my opinion they are not terribly expensive. The AMT / mid combo I have now cost less than 50% of a pair of dash speakers they replaced and are much better.
Negatives, well I'm not really sure just how durable they are in the automotive environment, hot cabin in the summer, cold in the winter, and dirty air compared to using them in the home. Mine are getting direct sunlight through the windshield and I have been expecting to see changes in the Kapton film, but none so far.
I'd say give them a try, but I would also recommend careful selection of the mid you use with it too.
Thanks for sharing, RiLoWa! I was considering those AMTs as well.
I'm looking to mount these in my a pillars behind fabric, so they should be shielded somewhat from the elements. You bring up good points, though, as they're fragile (apparently).
Might just have to give them a try. Worst comes to worst, I'll have (ugh... ANOTHER) set of speakers lying around that I'm not using. lol
Cheers!
I'm looking to mount these in my a pillars behind fabric, so they should be shielded somewhat from the elements. You bring up good points, though, as they're fragile (apparently).
Might just have to give them a try. Worst comes to worst, I'll have (ugh... ANOTHER) set of speakers lying around that I'm not using. lol
Cheers!