$100 ESS AMT3 rock monitors

I had it cranked for about 15min. It was damaged beforehand though.

I had the burnt l pad turned as low as it would go and still send signal.
 
My concern arises from the remote possibility that someone else along the way was not as prudent and deviated from factory original values. Without a known schematic, you'll never know unless you chart what you already have and do a bit of reverse engineering.
Can the software you have take a schematic and simulate it's potential output? If Jer was willing to work with us, I could send him out a small LC meter to take a reading on those coils and we could recreate the documentation that ESS seemed to lose back in the great Sacramento beer flood of '81.
Whoops, almost forgot the gratuitous shot of the girls playing in the living room.

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So iam reading alot here and wanted to know if the light color grill cover is original , mine are original brow/black and i want to change them to the one you have,also i need the capacitors for the AMT 3 rock which are 33uf and 51.5 uf any luck finding these
Mark
 
So iam reading alot here and wanted to know if the light color grill cover is original , mine are original brow/black and i want to change them to the one you have,also i need the capacitors for the AMT 3 rock which are 33uf and 51.5 uf any luck finding these
Mark
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The brown and black is original. I wanted a bit of a change and used a cloth called "Salt and Pepper" from Mojotone. It was popularized originally by Marshall amplifiers back in the day and is the most expensive cloth Mojotone has to offer. It figures that I would like it best.
33uF is a popular size and capacitor and is readily available just about everywhere. I had to parallel a 51uF with a .5uF foil bypass cap to total 51.5. Some would say that the 5.15 cap paralleling the woofer doesn't benefit from poly and foil caps, so you could save a bit of money (and space- those bastards are big as a pop can) going with electrolytic at that point. Some would argue that we're fooling ourselves with the polycap craze and we really can't distinguish between polycaps and OEM electrolytic caps. I've A/B'd the two on some other speakers and the difference wasn't earth shaking - a few of my judging panel actually preferred electrolytic, but they had a bunch of wine in them and I gave a SLIGHT edge to electrolytic.
For what it's worth.

Also shown is on monitor side grill in MojoWeaveBlue/Black and and one in Mojoweave Red/Black.

IMG_0491.JPG NewGrille2.JPG SideGrillBlue.jpg SideGrillRed2.jpg
 
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The brown and black is original. I wanted a bit of a change and used a cloth called "Salt and Pepper" from Mojotone. It was popularized originally by Marshall amplifiers back in the day and is the most expensive cloth Mojotone has to offer. It figures that I would like it best.
33uF is a popular size and capacitor and is readily available just about everywhere. I had to parallel a 51uF with a .5uF foil bypass cap to total 51.5. Some would say that the 5.15 cap paralleling the woofer doesn't benefit from poly and foil caps, so you could save a bit of money (and space- those bastards are big as a pop can) going with electrolytic at that point. Some would argue that we're fooling ourselves with the polycap craze and we really can't distinguish between polycaps and OEM electrolytic caps. I've A/B'd the two on some other speakers and the difference wasn't earth shaking - a few of my judging panel actually preferred electrolytic, but they had a bunch of wine in them and I gave a SLIGHT edge to electrolytic.
For what it's worth.

Also shown is on monitor side grill in MojoWeaveBlue/Black and and one in Mojoweave Red/Black.

View attachment 1412878 View attachment 1412879 View attachment 1412882 View attachment 1412883
Now i am getting very confused. Talked to Ricky and he told me to send the crossover back and they will rebuild them.
The problem is he states the speakers should have 2 ,10" 4ohm woofers in parallel and with a 6 inch mid at 4 ohms the circuit should be 6 ohms.
Problem is there is a shelf in the middle and so 2 10inch won't fit and still allow for the 6 inch mid.
My mind is trying to remember that i thought the woofers original were small for such a cabinet.
Ive asked Ricky if the crossover would be right for the 10 inch if the original were 8 inch.
And what ohm speakers ???
 
Now i am getting very confused. Talked to Ricky and he told me to send the crossover back and they will rebuild them.
The problem is he states the speakers should have 2 ,10" 4ohm woofers in parallel and with a 6 inch mid at 4 ohms the circuit should be 6 ohms.
Problem is there is a shelf in the middle and so 2 10inch won't fit and still allow for the 6 inch mid.
My mind is trying to remember that i thought the woofers original were small for such a cabinet.
Ive asked Ricky if the crossover would be right for the 10 inch if the original were 8 inch.
And what ohm speakers ???
 

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Now i am getting very confused. Talked to Ricky and he told me to send the crossover back and they will rebuild them.
The problem is he states the speakers should have 2 ,10" 4ohm woofers in parallel and with a 6 inch mid at 4 ohms the circuit should be 6 ohms.
Problem is there is a shelf in the middle and so 2 10inch won't fit and still allow for the 6 inch mid.
My mind is trying to remember that i thought the woofers original were small for such a cabinet.
Ive asked Ricky if the crossover would be right for the 10 inch if the original were 8 inch.
And what ohm speakers ???
It looks like you have the crossover pictured below. If you have two 33 uF capacitors and two 51.5 uF capacitors, the impedence of your woofers is 8 Ohms each. When they're paralleled with each other, that totals 4 ohms.
There was an AMT3 that came with a pair of 4 ohm woofers, but they were comparatively rare and the crossover below wouldn't work with that impedence. NOTE: On the crossover below, the term "MFD" is interchangable with uF. Both mean "Microfarad"
Although I've never heard of a rock monitor with 8" woofers, it's not the size of the cone that counts, with regard to the crossover. It's the impedence of the voice coil of the woofer. They're generally rated at 4 or 8 ohm. The original woofers for the crossover below (which I think is yours) were rated at 8 ohms.


CrossoverDrawing.jpg
 
That shelf in the middle of yours looks like a DIY add-in. Below is a more typical scenario (before I redesigned the the baffle setup entirely).

IMG_0170.JPG IMG_0169.JPG
 
If you know anyone with the ability to solder, the cost of the caps, if you go with original electrolytic, would be about 15 bucks. You'll also want to think of replacing the resistors - anyone who tells you that the resistors aren't a wear item and that "they look fine" because they're not scorched, isn't worth listening to.
 
That shelf in the middle of yours looks like a DIY add-in. Below is a more typical scenario (before I redesigned the the baffle setup entirely).

View attachment 1413068 View attachment 1413069
You are Awesome. That is the exact crossover.
Well I bought these from a friend who bought them new. I was the first to open them.
But i am fine with pulling them out . Do you have a drawing of the cutouts as o will have a customer laser cut them out of dieboard.
I will now have to send the one 10 4 ohm speaker arriving back to Amazon
You can also send directly to email mwlaser1@yahoo.com
 
AMT3 crossover with big, honking poly (L) caps before I decided to remount them on an auxillary board (R)



IMG_0087.JPG PCBoard_With_Old_Crossover.jpg
 
You are Awesome. That is the exact crossover.
Well I bought these from a friend who bought them new. I was the first to open them.
But i am fine with pulling them out . Do you have a drawing of the cutouts as o will have a customer laser cut them out of dieboard.
I will now have to send the one 10 4 ohm speaker arriving back to Amazon
You can also send directly to email mwlaser1@yahoo.com
Unfortunately, I don't have any drawings. When I re-did my baffles, I measured and re-measured and re-re-measured and drew everything directly to the wood, and then cut and shaved until I had a light friction fit with each individual enclosure. It was time consuming. The round cuts and recesses were all done with a plunge router and a circle jig.

IMG_0204.JPG
 
Unfortunately, I don't have any drawings. When I re-did my baffles, I measured and re-measured and re-re-measured and drew everything directly to the wood, and then cut and shaved until I had a light friction fit with each individual enclosure. It was time consuming. The round cuts and recesses were all done with a plunge router and a circle jig.

View attachment 1413107
Excellent. Thanks so much
 
Now i am getting very confused. Talked to Ricky and he told me to send the crossover back and they will rebuild them.
The problem is he states the speakers should have 2 ,10" 4ohm woofers in parallel and with a 6 inch mid at 4 ohms the circuit should be 6 ohms.
Problem is there is a shelf in the middle and so 2 10inch won't fit and still allow for the 6 inch mid.
My mind is trying to remember that i thought the woofers original were small for such a cabinet.
Ive asked Ricky if the crossover would be right for the 10 inch if the original were 8 inch.
And what ohm speakers ???


Only 8 ohm's were installed originally in your cabinets not any 4 ohm woofers and midrangers either. Ricky may not know that much on these as the 4 ohm won't work at all
 
Only 8 ohm's were installed originally in your cabinets not any 4 ohm woofers and midrangers either. Ricky may not know that much on these as the 4 ohm won't work at all
Ok learning alot here. Oh if you have any questions on high power lasers i can help.
Last question i cannot find markings on the caps as to direction and what woofer and mid range would you recommend.
Any way to test the Heil besides working or not?
 
Ok learning alot here. Oh if you have any questions on high power lasers i can help.
Last question i cannot find markings on the caps as to direction and what woofer and mid range would you recommend.
Any way to test the Heil besides working or not?

Audio capacitors are non-polarized, meaning their mounting direction doesn't matter.
AK ESS guru Automojo has had good things to say about the Eminence BP-102 I'd recommend the Dayton ST255-8, but they've been discontinued. There may be a few Eminence 1040SF's out there, but I think they're on the outs too - they were billed as a direct replacement for ESS 10" 8 ohm woofers.
The Eminence Alpha 6a is the heir apparent to the AMT-3's "transition driver". I think it's a step up from OEM, but it's got more oomf for the watt, so it needs an L-pad.

IMG_0175.JPG
 
Unfortunately, I don't have any drawings. When I re-did my baffles, I measured and re-measured and re-re-measured and drew everything directly to the wood, and then cut and shaved until I had a light friction fit with each individual enclosure. It was time consuming. The round cuts and recesses were all done with a plunge router and a circle jig.

View attachment 1413107
ok I will be removing the center shelf to handle the two 10 inch woofers. so what was the thickness of the baffle you used , I think 5/8 ? getting ready to lasercut
 
ok I will be removing the center shelf to handle the two 10 inch woofers. so what was the thickness of the baffle you used , I think 5/8 ? getting ready to lasercut
The original baffles were 3/4" presto log with a 3/8" rabbet joint routed on the edge so that it sat on the wall edges of the front of the inner enclosure. I put furring strips inside of the enclosure and mounted 1/2" Birch plywood on top of them. On top of that, It was 3/4" MDF, which brought the front baffle and drivers level with the edges of the inner enclosure. Over that was a piece of 3/8" particle board (light weight) as a decorative cover over the driver hardware. It's lightly glued on with silicone to bring it back to the position of the original baffle.
 
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