Smashed --.> ESS Heil Air Motion Transformer AMT Tweeter -- Anyway to fix these?

Plastic is cracked
ribbons are destroyed
I was thinking of replacing the ribbon
But it has some fancy type multilayer ribbon material


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Founder of XSA-Labs
Joined 2012
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That's a shame as those are world class sounding when intact. The problem is the plastic frame keeps the metal grille which provides the magnetic force uniform over the pleated diaphragm/membrane. The diaphragms are replaceable but with no frame to hold them...

If you have CAD and can access a 3d printer - make a new frame and transfer magnet assmbly over. Buy new diaphragm.

Try sending back to ESS for repair?


Disabled Account
Joined 2007
The plastic part can be replaced by either non-magnetic metal or 3D-printed plastic (ABS or similar). It can be repaired with epoxy too. ESS can repair the AMTs, diaphragms are also still available but they have to match the exact model/type, they were modified over time. In any case, it's worth the repair cost, AMTs are awesome drivers, extremely good resolution and amazing dynamic.
Actually I repair plastic with a soldering iron and zip ties (or some other plastic).
Make sure you use a fan, if you do this, right by your face and do it outside.
It 's very hard to glue plastic.
There's many different glues and plastics.
They never really glue right and some are really impossible to glue.
The only way you can glue plastically effectively, in my experience, is to chemically or thermally melt the plastic and let it solidify again.

Sounds like I can only get the ribbons from ESS
Different makes of the diaphragm used different materials, from mylar to polyethylene.

The fact that the forces are opposed makes gluing the assembly a sonuvagun. I once had a jackanape send me amt1s in USPS flat rate boxes.... that's it.... they were smashed to heck. This clown then took weeks to refund me for his uninsured, poor shipping, and had the nerve to give negative feedback over the transaction.


But yah, they'll be tough to get back together. I suggest a wooden jig to align them, put back together with epoxy, and keep some sort of structural support in place.


Disabled Account
Joined 2007
The diaphragms are $75 a piece
If they were half that I might buy them
If they were $50 I definitely would

The half of 75 is .. 37,50.. ;)

I'm hoping to make my own and kind of half *** it

Well, I pretty much doubt you'll get anywhere near a functioning diaphragm with DIY but go for it, I'd be happy to see me wrong if you'd succeed.
late to the party, and Jimmy has probably moved on, but:

Yes, the diaphragm on those is a not simple design, and the substantial mass of the stacked magnet assembly would require any attempted repair to the plastic housing to be very sturdy and very accurately aligned.

As xrk noted earlier, when properly functioning, the AMT itself could still be considered world class.

Having sold the ESS AMT1 back in the 70's when accompanying amps / receivers were often higher powered SS designs, I'd opine that the shrillness of which Mark speaks could have been a combination of the amps and the shall we say, rather "interesting" crossover design. With a better crossover design (starting with no BPE caps, and higher XO point), and when coupled with lower powered, and particularly tubed amps, the driver itself can be quite delightful to say the least.
Troels Gravesen said you could replace a ribbon for nothing in one of his Acapella Articles, but then forgot to tell us how it was done. :D

On his website he does have an article on replacing Fountek ribbons. I don't know if it helps. Don't you make them out of cooking foil? :xfingers:

He's a nice chap. Maybe an email. But tell us how you get on.
I probably won't have the time to make these ribbons.
But I will keep looking for replacement I can "make" work.
Because you can ask $80 for a 5 cent ribbon and of course that is okay and often justified, even though no justification is needed.

BUT I can guaranty that these or similar ribbons exist for $10, maybe 20/pair shipped to my door, since that person is sill making quite a good profit.

I just like this magnet structure and design. But I can get a similar ribbon (and a small magnet driver) for $30/pr.