ESS AMT-1 in my projects

So I've continued a bit with the "Heil Horn" design (that name sounds admittedly a bit "wrong), trying to "church it up" and make it a bit prettier. I modelled this tractrix-like horn that converts the original tall, vertical slot into a circular tractrix horn, which was no easy job to model. I'd like to make half of the horn out of wood pedals, and the back half likely 3d printed - however, the fabrication on this is going to be a challenge and before I spend lots of hours on the CNC I am going to 3d print it and take some FR measurements just to see what it does to the sound. It's about 6 big 3d prints so it will take some time, but I'm hoping it will give me a good enough impression to know whether to actually go through with the design. Unlike other wood pedal horns, which have any number of identical petals, this one will ultimately have 5 unique shapes I need to fabricate, which means 5 jigs and 5 hold downs, so it would be no easy task. However, if if it mates well with the heil it might be worth the effort.
 

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I use ESS AMT's atop KRK V88's. Similar to the ESS "Rock Monitors".
The internal plate amp is not used but this set is bi-amps with a custom PP tube and a KT88 amp.
A DBX 234 crossover splits the frequency.

Great mid punch and those ESS sparkling highs.
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My ESS AMTs on 17 l bass reflex with SB Acoustics MW16P-4 midwoofer, active crossover (W11 PC with Jriver Media Center and Topping DM7 8-channel USB DAC) 800 Hz/24db. Heavy boxes made with constrained layer damping. The reflex tubes are now clogged with socks, the LF down from 80 Hz is done by my Woofsorber. I'm more than happy with that.
 

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@xrk971 - I noticed on your MEH with the Heil (I think post 24 of this thread) you only used a single midrange/midwoofer in the assembly, where as many of the MEH designs I've seen use multiple (2-4). I'm kicking around the idea of just simply replicating that in concept but utilizing it in a tractrix horn, so that I could potentially do a 3 way system with a bass-bin on a hypex module with the MEH as a passive crossover that could be driven separately. I know you said that it was one of the better speakers you had ever heard at any cost, so rather than reinvent the wheel I'm going to follow in your footsteps.

Also - it appears that you have a pair of slots on the top of the horn for the mid injection? I was thinking it would make sense to keep the mid on the top or bottom since the dispersion of the Heil is largely horizontal. Do you recall about what their size was?
 
Since this is the most current thread regarding the Heil AMT, I have a question. On an open baffle application, does it matter if the configuration is TMM (2-1/2 way) or MTM? I've seen examples of both, but more TM/TMM layouts, especially open top mounted, like the pic above. I'll be starting out using Beta 8As for mid range (got four from the Madisound hot deal). The way my current baffles are setup, MTM would place the Heils right at ear level. TMM just a few inches higher.
 
Thats sorta how I got here. Started out with Li-Audio Fast 15s in a test baffle. Soon realized I needed more top end. So bought the Heils (on sale), also some Beta15As. Then one of the Li drivers started distorting, so picked up the Eminence Beta 8s. It all will be active, using a MiniDSP Studio SHD and some separate DACs and amps. Still need to order some protection caps before I try the Heils.
 
I bought a pair of ESS AMT-1 and really the sound of the AMTs above 7k but they sounded thin below that. So I built these 15 years ago.

The woofs are Lambda TD-15Ms and the mids are tractrix horns with JBL 2441 CDs and the AMTs as tweeters. The crossovers are at 700hz and 7khz.

I’ve still not heard speakers that sound better. To my ears of course.

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