ESS amt 1 tower drag home

Nice find, I hope everything works out.
But, I have to agree with Nexus. The TL cabinet was tailored to the original driver specs.
GOOD LUCK!
 
Nice find, I hope everything works out.
But, I have to agree with Nexus. The TL cabinet was tailored to the original driver specs.
GOOD LUCK!

I feel the same but I can't even find a picture of originals other than the one Porkloin posted. So I'm going to plan to get substitutes and keep a lookout for the ones Porkloin posted, keeping both if I ever find originals.
 
So that's where my yang is, I knew it, I don't like the cold weather there either. I've seen a few old ESS woofers for sale, same look and design as the 690-0007 but not the right ones so far. I'm just going to make sure not to do any mods to the cab I can't undo if I don't put originals in.
 
So that's where my yang is, I knew it, I don't like the cold weather there either. I've seen a few old ESS woofers for sale, same look and design as the 690-0007 but not the right ones so far. I'm just going to make sure not to do any mods to the cab I can't undo if I don't put originals in.

Contrary to the popular sentiment that ESS in no way engaged in any sort of marketing expediency and sold speakers built with the utmost in engineering integrity, I think most modern quality drivers of the right impedance and size would give you as good a sound as the original woofer. The challenge would be to one up ESS (in the 70's) and actually perform the calculations to find a NEW driver that was actually more optimal for their transmission line than they did. The problem is that calculating transmissions lines is 1/10th theoretical and 9/10ths trial and error. The comparatively static rules from Thiel and Small regarding sealed and ported enclosures are much easier to live with. Who can afford to buy a bunch of drivers to install and test?
By the way, Seattle is the moderate climate capitol of the NW, right up there in livable weather with San Diego or Perth, Australia.
 
Oh yeah, Seattle, I was thinking Idaho, the Dakotas, my ADD type of reading is annoying. I've always wanted to check out that rainforest there on the coast. I've been looking at resistors, what's so fancy-pants about the Mills brand? Is there still a wound wire going through it? I've never ordered or replaced a resistor btw. I think I will go to the Fry's Electronics here first before I order, they will probably have what I need there. I need to call ESS about the woofers, they have called here twice now. I have too many projects going.
 
Oh yeah, Seattle, I was thinking Idaho, the Dakotas, my ADD type of reading is annoying. I've always wanted to check out that rainforest there on the coast. I've been looking at resistors, what's so fancy-pants about the Mills brand? Is there still a wound wire going through it? I've never ordered or replaced a resistor btw. I think I will go to the Fry's Electronics here first before I order, they will probably have what I need there. I need to call ESS about the woofers, they have called here twice now. I have too many projects going.
The Mills and the Dayton sand-cast are both wire-wound. The Mills' are a higher end product - one may not be able to hear the difference between the two, but anyone can appreciate the durability of the better product. I used them in a crossover project for their physical dimensions as i couldn't get sand-cast the same size as the originals, but I doubt that they made an audible difference.
You won't find much in the way of audio resistors or caps at Fry's, unless they have better project departments at other stores. My job demands that I visit Fry's twice a week as they're great for cheap computer components, but I've had to go to PE for speaker stuff.

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i recall a sales brochure for the the AMT tower which mentioned utilizing the original AMT woofer and "extracting every bit of possible performance from it" by the t-line loading. if you can find a 10" pulled from the original AMT it would most likely work (though you would probably have to re-foam)
 
I refurbished a pair of AMT-1 Towers two years ago. Here's what I did:

Replaced the woofers with OEM from ESS
Ditched the crossover and bought a used Behringer electronic crossover (much better and only $50)
Purchased new Heil diaphragms from ESS
Covered the speakers with fresh speaker cloth (you can choose a more modern looking fabric)
Paired them with a 15" subwoofer

Very happy with the sound.
 
I think like you do Porkloin, I like getting the best if I can afford it. I know people that buy cheap stuff, like tools. They keep having to buy another tool a few yeas later so why not just get the best that might last a lifetime. No reason to go cheap to literally save a few $ here.

I would really like to do that nexus, I want to find original woofers, I've been looking AND in the mean time go the mojo route, minus the subwoofer and a new xover. Bass, I like bass but enough for me isn't a lot. But I don't know, I will have to let my own ears decide there, I have no idea what these sounded like when new. I read yesterday of somebody putting in a Zu Audio woofer, but aren't those 8 ohm? I like the idea but I don't think the ohms fits the xover, going by what porkloin pointed out earlier about the Realistics that were in the cabs.
 
I'm at the AMTs again and have the crossover out on one. I have a confession, this is my first cap job and I don't know what to order.
One says 33uf-75VNP
... 51.5uf-75vnp
and 75mfd 75vnp

I go to a site like PartsExpress but I don't get the exact numbers, do they translate to something else? I took pics of everything so I know what went where. I really need some guidance in exactly what to order, it freezes me up looking at all that's available at PartsExpress.
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I was recommended these from the associated co. The outside diameter of the hole is 10.5" on the cabs. I still haven't called ESS but I will. Everybody is trying to make a sale so it's hard to know what will work best.
https://www.parts-express.com/goldwood-gw-10pc-4-10-heavy-duty-woofer-4-ohm--290-322

https://www.simplyspeakers.com/boston-acoustics-style-replacement-woofer-w-1010.html

Now I see the fuse holders I ordered don't quite fit in the mounting hole, have to look for some that fit or drill out a little which I'd rather not do.
 
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Over-kill I suppose but I'm trying to keep all parts that don't really "need" replacing. I ordered new rotary switches but I'm trying to save the originals. The rivets were getting loose on the switch, the JB is not original but the bead should keep the rivets from rotating. I also found the deoxit grease at Fry's, prob good stuff.
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I have the screws out but the white putty sealant used around the speaker cage is a little more than putty strength, it might be difficult to get them out but I'm going to work on it. These things are practically glued in but I'll get them out. What was the sealant like on the originals, it might be a clue also. But, doesn't matter, I'll get one of these out so we can see. imo the cone has an Advent look to it.
For the love of all that is holy, DO NOT make the same mistake as the manufacturer or any previous owners did and glue anything that may need to be removed in the future. The internet makes readily available all sorts of cool, DRY ways to cushion/seal things together.

Closed-cell foam and Buna-N rubber, to name a few.

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I'm at the AMTs again and have the crossover out on one. I have a confession, this is my first cap job and I don't know what to order.
One says 33uf-75VNP
... 51.5uf-75vnp
and 75mfd 75vnp

I go to a site like PartsExpress but I don't get the exact numbers, do they translate to something else? I took pics of everything so I know what went where. I really need some guidance in exactly what to order, it freezes me up looking at all that's available at PartsExpress.
GQDWDgN.jpg

kDdX46p.jpg

zOYZHVA.jpg



I was recommended these from the associated co. The outside diameter of the hole is 10.5" on the cabs. I still haven't called ESS but I will. Everybody is trying to make a sale so it's hard to know what will work best.
https://www.parts-express.com/goldwood-gw-10pc-4-10-heavy-duty-woofer-4-ohm--290-322

https://www.simplyspeakers.com/boston-acoustics-style-replacement-woofer-w-1010.html

Now I see the fuse holders I ordered don't quite fit in the mounting hole, have to look for some that fit or drill out a little which I'd rather not do.
You can parallel multiple capacitors together to get the desired value. For example, you could twist the leads of a 50 uF cap with the leads of a 1.5 uF cap to get the desired value of 51.5 uF. The linked caps are electrolytic. Poly caps are considerably bigger and more expensive - in the case of the large cap ( 75 uF - 68 uF+ 6.8 uF) in the woofer leg, a poly cap would be money wasted as the lower frequencies don't benefit from poly-caps.
The 33 uF cap is probably the filter cap (if not ONE OF the filter caps along with the 51.5 uF cap) for the Heil. The Heil could benefit from the poly-cap, but it is 10 times the cost of a comparable electrolytic of that value.
I had to drill out my fuse holder hole a bit also. I used a step bit (the smaller of the two, if you have the two popular sizes).
 
Yeah I'm not gluing anything down like it was. The riveted down rotor connectors, just not meant to be serviceable and were starting to rotate, that will work and a cheap part. OK, going to have to figure that out with the caps, thanks a lot for that info. Yeah, I'd be lost without that info there They have an aisle of caps and resistors at the Fry's here, and the right size fuse holder, I'm going to check and get what I can there before I order anything again, might be wasting my time in that store but I'm going to check. After trimming the glue from the speaker hole which was easier than I thought it would be, and filling lifted areas around the speaker hole with wood filler, I see now that the OD is exactly 10.5". I'm going to call ESS tomorrow. I found the correct black paint, I can spray it on, let it dry and nobody could tell it was sprayed there. I first didn't realize you took the time to make links so I'm going to order and I'm going to get the better poly-cap.

I'm spending way more time on the cabs than I thought I would. I think it's because I have a hunch I will like these and keep them. I didn't like the edges on the cab, they say, "Hey, over here, look at me, I'm particle board!" I smoothed out wood filler over every edge and filled every staple hole, I don't think I will have the covers on often. This little dude showed up and was bothering me on the porch while I was messing with the cab, big centipede ran under the cabinet.
This was bugging me:
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Good on you. Those 70's cabinet were never anything to write home about. I spent a bit of time sanding and filling until everything was flat and didn't look particle-boardy also, only it didn't attract centipedes like yours appeared to.
 
The 51.5 uF capacitor not only acts as a parallel capacitor for the woofer, but the first in a series of two filter caps for the Heil. It's what is called a "third order (18 db per octave) high-pass network. The question is: does that cap need to be a poly-cap also to get the total benefits of poly-caps for the Heil? A 50 uF poly-cap is pricey and big enough to house a family of pikers and their pet centipedes. I wish I could say I knew the answer to that question, but it's obvious I don't as I did my whole project in poly-caps, with foil bypass caps to boot. I didn't like the way those monsters looked on the original crossover board, so I mounted them on a remote board (a Eurocard).
On the positive side, the 75 uF cap is part of a Zobel network, which maintains the impedence level on the woofer side and I doubt very much that it would benefit from a poly-cap in that location.

IMG_0088.JPG PCBoard_With_Old_Crossover_REDUCERD.jpg
 
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Good lord who ARE you! You know what that looks like to me? ...dangerous! I'm going to study this more, I'd love to feel like I know what's going on, to understand it better. I was just happy to get the caps out with my iron, "Wow, look at me!" When I get the new caps in and they work, that will be a good thing. The guy I bought them from said he couldn't get a sound out of either one of them. I do have giant centipedes in containers in the house, captive born. I started catching bugs when I was 2, still a kid 5 decades later. But I also sell that stuff to a pet store and on the internet, sometimes.
 
Good lord who ARE you! You know what that looks like to me? ...dangerous! I'm going to study this more, I'd love to feel like I know what's going on, to understand it better. I was just happy to get the caps out with my iron, "Wow, look at me!" When I get the new caps in and they work, that will be a good thing. The guy I bought them from said he couldn't get a sound out of either one of them. I do have giant centipedes in containers in the house, captive born. I started catching bugs when I was 2, still a kid 5 decades later. But I also sell that stuff to a pet store and on the internet, sometimes.
The "eurocard" was actually an easier way to deal with the big, fat caps than attaching them to the original PC board. You had to be able to solder to a PC board either way. The difficulty with the eurocard was the patience needed to lay it out. Then it's just a matter or running wires from cap circuit on the eurocard to it's respective capacitor holes on the original PC board.
it's so easy, even a centipede could do it.
 
I have one of those cards, bought it a Fry's a long time ago to repair something else. One of the original capacitors is 51.5uf but Parts Express does have a 51uf poly-cap. How important is the .5uf, would I miss it? I guess the .5 is there for a reason so I feel I should install 51.5uf like the original. What do you think there? I thought I might be getting OC with the cabs but I think it's paying off. Spray paint sucks and I forgot I knew that ..."roller Todd! roller!" Maybe I'm just not good with spray paint. So much easier, faster and looks better using a roller on a flat surface.
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