View Full Version : ESS AMT1B Pyramid Refurb, Help!


Artifact
11-23-2011, 03:22 PM
I am starting a refurb of my ESS AMT1B pyramid speakers including a refoam of the woofers and PRs, new diaphragms for the Heil AMTs and new capacitors for the cross overs. Unfortunately, I have a 1” tear at the periphery of one of the “Bextrene” woofer cones. Is this repairable in some way or should I consider replacing with aftermarket woofers or the new ESS treated paper replacements? (available at Parts Express or directly from ESS). I don’t have a huge budget and the new ESS speakers are about $300 for the pair, plus 12% tax, plus $52.00 shipping. Suggestions/Recommendations greatly appreciated!
John

automojo
11-23-2011, 04:37 PM
Ess may be able to recone these- they used to run a exchange on these.
Possible they are repairable-I would post a pic.
Personally I would leave the refoaming of those to a pro-since they are brittle.
You could replace them with the paper cones-but I would look at repairing them first-since only one is damaged.
Call ESS-or alternatively Simply Speakers- or Orange County speakers and weigh your options-but let a pro do the refoam of the other one....

bobrown14
11-24-2011, 08:33 AM
You should be able to source a replacement woofer on the 'bay. I did that and it cost me $56. Probably cheaper than getting it fixed.

Cheers,
Bob

automojo
11-24-2011, 11:32 AM
Make sure the numbers match if you get a used one-as some ESS Bextrine woofers used whizzer cones under the dust cap to aid on transition from the large driver to the Heil.
Personally if I had the cash- I would go with the new paper cone drivers as in my experience they are a much better match with the Heils.
Not only in efficiency, but in tonality and detail as well. At least the Bextrines don't have that 'snap" that poly woofers have, or the sheen of carbon fiber woofers.
What they all miss over the paper cones is those little fine details, ones that get smoothed over by the plastic cones.
Guitar string scrapes, creeks, scrapes etc. Lucikly the detail doesn't come at the price of exaggeration, or strange overemphasized detail/weird tonality of some of the new speakers.
The draw back is that they require a bit better equipment matching, and 'tell it like it is' character might not be to everyones liking, but that doesn't bother me- I'll stick with the detail.

wizargoz
11-24-2011, 11:43 AM
Not to derail the thread, but has anyone here bought the replacement paper woofers from Parts Express (for the ESS 1B)? I'm tempted, but it would be $300+ for 2 of them, so the question would be does the cost justify the performance?

Artifact
11-24-2011, 12:53 PM
I spoke with Ricky Caudillo, the CEO at ESS yesterday. Reconing the existing woofers is $100 each plus shipping to ESS and shipping back to me again. Have therefor decided to get the new treated paper woofers at $140 each plus shipping. I may also go for new Heil diaphragms at $80 each although Ricky stated that if the wiring in the existing diaphragms seems "straight" (in vertical alignment?) I shouldn't need them. However, reviews of the replacement diaphragms on Parts Express seem to indicate that replacements make a huge difference in sound...
Next step is figuring out what caps I need for the crossovers. Being a relative newbee I'm trying to research info on series vs parallel configurations and things like bypass and cascading capacitor configurations. "diamondsouled" did his crossovers recently but I don't quite get what he has done. Has he simply piggy backed and joined the wires of the new caps to make up the original capacitance? (Yes this stuff is well over my head, but I do have lots of time...) See below:
http://mail.audiokarma.org/forums/attachment.php?attachmentid=132106&d=1233123248

Artifact
11-24-2011, 01:03 PM
For your info diamondsouled's original thread re caps is located at: http://mail.audiokarma.org/forums/showthread.php?t=207138

automojo
11-24-2011, 01:20 PM
I'm very interested in hearing how those new ESS paper woofers sound.
As far as caps-try to get values close as possible, and then paralell the smaller cap to reach the end value.
This is easy-just take the smaller cap, and wrapp each lead to the smaller cap (try to do this close to where the leads exit the larger cap to leave enough room for your final connection).
ESS used a 10% tolerence in the O.E. crossover-but these speakers will benefit greatly from using tight tolerence caps (and inductors for that matter).
Erse PulseX are a good choice, and hard to beat the prices-direct from Erse.
and have a 3% tolorence. They tend to be a little shorter then P.E. polys and Solens-which can be helpful.
Designer caps won't get you any real improvement in sound-perhaps different do to a 15% tolerence swing (in some instances), and many have a alarmingly high ESR. I wouldn't recommend paper in oil or the like.
What your trying to do is get the crossover back in spec and reduce ESR-not change the way it sounds with weird capacitors. Using those designer caps-such as paper in oil/etc- would IMHO call for a modification of the original O.E. design to account for their deficiencies.
Bypass caps-well I won't get into that one-as it's a mix of electrolytic and ploy's-a price saving/benefit issue.
The benfit from using poly's vs electrolytics is two fold-longer life (you shouldn't have to redo them in your lifetime) and low ESR-which does make a difference in how the crossover performs, it's interaction with the driving amplifier, as well as the overall efficiency of the speaker. All good things.
Their should be a schematic of your speaker some where on AK-if not I may have one. I would use this as a referecne to keep from getting mixed up- which is easy to do-believe me!!

Mchaz
11-24-2011, 01:34 PM
Capacitors in parallel, e.g. piggybacked with the wires on both ends joined together, have a total capacitance equal to the sum of the individual capacitors. In other words, just add the two capacitor values.

automojo
11-24-2011, 01:50 PM
As far as the diaphrams go- I would try the O.E. first- These large AMT diphrams are really hard to kill in my experience.
Keep the tweeter circuit fused and you will be fine.
I wouldn't go on the looks-that small part you can see through the opening as a indicator of it's performance or condition unless you can see a break or tear.
Mixing different type of diaphrams can yield different outputs in some cases. The reohstats can make up for it-but best avoided IMHO.

wizargoz
11-24-2011, 02:26 PM
Keep us tuned, Artifact. Thanks!

automojo
11-24-2011, 02:53 PM
From what I have read there seems to be some debate on which diaphram types a 'better' then others, and no clear cut information IMHO.
ElSeven did post he had measured the outputs of the newest diaphrams vs old, and there was some difference in the output, but other have commented different.
My 2 AMT3's all have the 74 + era clear diaphrams, and this including one 'spare' AMT I have and 3 extra diaphrams-so I couldn't compare the 2.
Some alos think the older design AMT with the narrower opening is superior.
Not sure on this one either.
Regarless see if the old ones are functioning properly before you spend the extra cash on something that might not improve the sound. The older diaphram, as I can atest to are perfectly fine.
Keeps us posted, as I'm really very curious on those new paper cone woofers.
Up to now the OCS 1040 sf as been one of few really compatable options for replacing ESS O.E. woofers.
Thos woofers could work with the AMT3, but would require some modifications due to their frame shape not being totally round on the new units-the AMT3's I have seen all used the tradition round 10" paper cone woofers usually CTS ALnico types.

Artifact
11-24-2011, 04:57 PM
Many thanks for all of your input. I will definitely let you know how the new woofers sound when I get them up and running. More questions....

Question1: Is there any advantage to piggybacking two caps to get the cap value of the original if you can get just get one cap that equals the value of the original?

Question2: I have heard that some people piggyback a more expensive small value cap on a cheaper larger value cap to get either an improvement or adjustment in sound quality. For example to get a 33mfd value, you might pair a ClarityCap SA 30mfd with a Mundorf Supreme 3mfd. Don't think I will go this route owing to the cash layout required but thought I'd ask anyway.

Question3: Is it OK to mix different voltages of capacitors in the crossover either singly or when piggybacking?

The cap values I need are 33 and 10.

automojo
11-24-2011, 06:19 PM
The advantage is the cheap cap takes on all the advantages of the smaller poly cap. Personally I would stick with the polys-and a single cap is one less connection-a good thing.
Not trying to make this a cap type argument, but a tight tolerence poly and electrolytic-on the ESS AMT3's anyway-won't make any audible difference-I have two pairs one that has new tight tolerence electrolytics, and one that I experimented with adding just tight tolerence polys-can't tell the difference. Nor could any one else. Replacing out of spec/leaking caps is what makes the audible difference-plain and simple. CHanging the tolderence or values changes the way the crossover behaves electrically-it's points-that makes the audible difference. The rest IMHO is snake oil.
Although the satisfaction value of those exotic looking and costly caps for some may be worth it-the intangable benefit I suppose.
As mentioned-poly's offer low ESR and long life-that's why I would suggest them.
Those values should be easy to find in all caps. Nothing wrong with mixing voltages- the larger one will usally have thicker leads.
I would strive to get as tight of ntolerence as possbile 3-5%.
Aloso touch up/redoe all the connections you won't be installing new caps into.
Also replace that resitors, as I have found a few O.E.'s flaky, and/or brown. Mills, or Daytons are fine.
I would also suggest rewriing the driver leads with new wire, as they are easy to get to.

Artifact
11-25-2011, 01:48 AM
Thanks for all the knowledgeable and insightful tips automojo! I'm assuming that higher voltage caps store up more energy for major transients and are probably the wise buy for the ESS?

automojo
11-25-2011, 10:36 AM
Thanks for all the knowledgeable and insightful tips automojo! I'm assuming that higher voltage caps store up more energy for major transients and are probably the wise buy for the ESS?

If you can fit them in, I don't see a problem with them. The higher volts caps are made to handle higher input power (watts), larger amps, without sustaining damage. They don't store any more energy then a equivelent cap of the same value-but lower voltage rating.
100 volts is usually fine for most applications-but I usually go with 250 volts to be on the safe side. 400 volt on up are usally for prosound applications.
I usually buy my caps directly from Erse-they happened to be out of the 250 volt 51uf cap, and asked me if they could sub a 400 volt cap. I said sure, since this was a custom crossover-it's bigger for sure-with larger leads-but there won't be any sonic advantage to having the larger cap.

Artifact
12-03-2011, 01:11 PM
UPDATE: Have ordered 250V Mundorf M-Cap MKP capacitors to replace the existing caps on the ESS AMT1b's. Seemed the best compromise between quality vs cost for replacements. Since space is at a premium, it also helps that they are small compared to almost all caps on the market. Owing to cramped space on the circuit board I will need to run additional wire from the capacitor wires. The cap wire diameter is 1.0mm which translates to 18awg hook-up wire. Should I stick with 18AWG or move to a slightly larger wire? Should the hook-up wire be solid core or stranded type or does it matter?
Am also wondering: what is that softish translucent brown substance that was originally used, in huge amounts, to glue down the inductors (rubber cement?) I may need to move 2 of the inductors over a bit to make room for the caps.
Thanks for input!
John

bobrown14
12-03-2011, 07:02 PM
UPDATE: Have ordered 250V Mundorf M-Cap MKP capacitors to replace the existing caps on the ESS AMT1b's. Seemed the best compromise between quality vs cost for replacements. Since space is at a premium, it also helps that they are small compared to almost all caps on the market. Owing to cramped space on the circuit board I will need to run additional wire from the capacitor wires. The cap wire diameter is 1.0mm which translates to 18awg hook-up wire. Should I stick with 18AWG or move to a slightly larger wire? Should the hook-up wire be solid core or stranded type or does it matter?
Am also wondering: what is that softish translucent brown substance that was originally used, in huge amounts, to glue down the inductors (rubber cement?) I may need to move 2 of the inductors over a bit to make room for the caps.
Thanks for input!
John

Leave the indutors in place and add some wire to extend the leads. I use hot glue to glue down the new larger caps. For extension wire either will do, solid or strand use what you have in hand. 18 gage is fine but again use what you have ....
Cheers,
Bob

Artifact
12-04-2011, 11:52 AM
Leave the indutors in place and add some wire to extend the leads. I use hot glue to glue down the new larger caps. For extension wire either will do, solid or strand use what you have in hand. 18 gage is fine but again use what you have ....
Cheers,
Bob

Thanks Bob!
John

automojo
12-09-2011, 10:03 PM
The brown glue is hot melt. A hair dryer will soften it-but you should be able to reattach it.
18 gauge tinned hookup wire is fine. If you have 15 or 14g auge lying around use it.
Those cap should be just fine.
Make sure you replace the resistor(s) as well. Found a few suspect ESS resitors, and they are cheap-even the Mills-so I would recommmend it. You can just glue the new one on top of the old one. Cut the old resitors lead flush to prevent a short/etc. Silicone will work, or epoxy to glue the new one on top of the old. You can also glue a small piece of wood between the two to create some air space and aid in cooling.

Artifact
12-10-2011, 03:08 PM
The brown glue is hot melt. A hair dryer will soften it-but you should be able to reattach it.
18 gauge tinned hookup wire is fine. If you have 15 or 14g auge lying around use it.
Those cap should be just fine.
Make sure you replace the resistor(s) as well. Found a few suspect ESS resitors, and they are cheap-even the Mills-so I would recommmend it. You can just glue the new one on top of the old one. Cut the old resitors lead flush to prevent a short/etc. Silicone will work, or epoxy to glue the new one on top of the old. You can also glue a small piece of wood between the two to create some air space and aid in cooling.

Thanks for the info automojo. I had forgotten about the resistors and will probably order some today. The info on the existing resistors is 7328 IRC PW10 4ohm 10%. I assume this simply means 10 watt 4ohm 10% tolerance?
I have received all the other stuff I need for my project including the Mundorf Mcaps, new ESS woofers, and new binding posts (never replaced the originals until now.) I'm now pondering what to use as damping material in the cabinets. I filled them with accoustistuff last time I did a refoam but was disappointed in the resulting bass response. I think the accoustistuff interfered with the interaction between the woofer and the passive radiator. I'm considering just lining them using either 1/2" felt, 2" fiberglass or possibly open cell foam - or a combination....

sealy
12-10-2011, 05:24 PM
I'd go with a paper woofer. Bextrene cones are heavy by comparison and consequently slower in the bass region.

Artifact
12-10-2011, 06:14 PM
I'd go with a paper woofer. Bextrene cones are heavy by comparison and consequently slower in the bass region.

Hi Sealy, the new 12" ESS woofers that I bought are made out of treated paper. You can see them at: http://www.parts-express.com/pe/showdetl.cfm?Partnumber=264-622 They are also available in a 10" version. Hopefully they are significantly better than the Bextrene ones. Cheers!

automojo
12-10-2011, 08:37 PM
I would go with what ever ESS had in those cabinets-as the stuffing is part of the cabinet tuning, along with absorbing back waves/standing waves.
AMT3's are plumb full- and I found you don't want to vary the amount of poly fill at all.
Some of the AMT1's had a sack of sorts to keep the stuffing with interfering with the airway between the passive and woofer.
You may want to also want to consider lining the siade wals with Sonic Barrier (1/2-3/4 inch) as this will also reduce back wwave reflections and help clear up the midbass area-tighten things up.
RonC I'm fairly sure has a pair of these- and could probably help you out with stuffing/damping ideas-he has done some excellent work in this area @ AMT3's.

Artifact
12-10-2011, 09:32 PM
I would go with what ever ESS had in those cabinets-as the stuffing is part of the cabinet tuning,

I have been trying to remember what stuffing was in them when I last refoamed them but that was about 10 years ago and my memory isn't getting any better.... I think it was pretty minimal and fiberglass.
I'll try to get a hold of Ronc to see what he has done with damping materials.

Can you confirm that my resistor's are 10 Watt 4 ohm as per the description in my previous post. Much appreciated.

automojo
12-11-2011, 09:23 AM
I have been trying to remember what stuffing was in them when I last refoamed them but that was about 10 years ago and my memory isn't getting any better.... I think it was pretty minimal and fiberglass.
I'll try to get a hold of Ronc to see what he has done with damping materials.

Can you confirm that my resistor's are 10 Watt 4 ohm as per the description in my previous post. Much appreciated.

I don't have a crossover schematic of that speaker-but 10 watt values are fine-you will just have to confirm the 4 ohm rating- but that seems about right.
That resistor in you posted pic looks like a typical ESS O.E. resistor.

ron-c
12-11-2011, 01:38 PM
Cabinet dampening material, I have yet to regret ever using Sonic Barrier to line the inside of the cabinets. Some models have fairly thin and lively walls like the front and back panel of the AMT3. If you can swing the cost the 1-1/4" stuff is the best. Sonic Barrier will quiet the panels and make the cabinet appear larger to the driver giving cleaner bass. Before you install the SB it is always a good idea to clean everything out of he cabinet and glue/seal all seams. In the AMT3, and Monitors you can also run screws in from the inside to the outside panels so they are tied together.
SB is NOT a replacement for the stuffing in the cabinet. You can reuse the stock packing or the better Acousta Stuff from Parts Express. Whichever you use make sure you 'tease' it so it consistent density. If you are using one of the models it is best to keep the packing from laying up against the passive radiator as this will impede its function.
On the older models using 8mm bolts and t-nuts to hole the woofers in. I always epoxy the T-nuts in and line the woofer mating surface with a thin coat of epoxy to seal the woofer mounting particle board surface. Make sure the epoxy is completely dry and use a thin gasket under the woofer before mounting it in the cabinet.


Thanks again,
Ron-C

ron-c
12-11-2011, 01:52 PM
Crossovers, having all of the parts in value is important and the stock caps on the older speakers are usually shot after all this time. Defective parts put the speakers and diaphragms at risk since they may no longer be crossed over properly. If you are going to spend some money on better or bigger parts remember that some of the new, large, low resistance crossover coils will translate to noticeable speaker efficiency in cease which is a good thing.
Please see attached pictures of two AMT3 crossovers for an example. The big parts are mounted on a sheet of plastic from Tap Plastics.

Thanks,
Ron-C

automojo
12-11-2011, 04:06 PM
Great info-thanks Ron!:thmbsp:

Artifact
12-12-2011, 04:07 PM
Cabinet dampening material, I have yet to regret ever using Sonic Barrier to line the inside of the cabinets, etc.
Ron-C

Thanks Ron-C, I did a quick calculation on what it would cost me to get 8 panels of 1" sonic Barrier to Canada from Parts Express. Worked out to about $225.00 with shipping, tax, duties and other service charges. The 1 1/4" would be almost twice that amount, unfortunately out of my budget… I'll check locally for cheaper open celled foam or go with something else. I'm definitely going to implement your other suggestions however. Have started to reglue all cabinet seams. In addition to gluing are you suggesting a latex or silicone sealant as well?
Thanks again, much appreciated!

Artifact
12-12-2011, 04:26 PM
I don't have a crossover schematic of that speaker-but 10 watt values are fine-you will just have to confirm the 4 ohm rating- but that seems about right.
That resistor in you posted pic looks like a typical ESS O.E. resistor.

Thanks automojo, I ordered a couple of Mills 3.9 ohm 12W 1% resistors yesterday! - should be fine. Originals were 4 ohm 10W 10% tolerance

automojo
12-12-2011, 10:30 PM
Thanks Ron-C, I did a quick calculation on what it would cost me to get 8 panels of 1" sonic Barrier to Canada from Parts Express. Worked out to about $225.00 with shipping, tax, duties and other service charges. The 1 1/4" would be almost twice that amount, unfortunately out of my budget… I'll check locally for cheaper open celled foam or go with something else. I'm definitely going to implement your other suggestions however. Have started to reglue all cabinet seams. In addition to gluing are you suggesting a latex or silicone sealant as well?
Thanks again, much appreciated!

I did both, as silicone is realitively cheap, and it's good to know you've almost 100% sure stopped any air leaks in the cabinet seems.
I see they have some brush stuff seam sealer-but it's usually pretty potent smelling stuff-solvent based.
I just bought the large tube sealer, and used a acid brush to apply it/smooth it into the seams.
It can be a bear working inside the cabinet in some of the areas to address the seams. I managed to some how get a nice blob of epoxy in my hair dealing with my second set!:sigh: Luckily I used the slow dry stuff, and a quick shower and all was good.:thmbsp:

automojo
12-12-2011, 11:53 PM
That's too much from P.E.
If your cabinet walls are fairly non resonate-then you can save the money and avoid the composite material. The foam is to absorb/diffuse soundwaves(standing waves/back waves) and to prevent reflections, while the vinyl decouples the foam from the enclosure- but also adds mass to the walls and changes the rate and freqency that they resonate at.
None of it really absorbs large standing bass waves much -because you would need the material to be very thick. But it will help break them up, in addition to absorbing the higher freqencies and prevent them from interfering with woofer or passive radiator.
I'm sure there is a acoustical/foam manufactor in Canada.
Solen/Ca has a few things.
Since yours is a passive (vs ported) system, you could use fiberglass 'boards' or squares (basically compressed fiberglass) in your enclosure.
The fiberglass will probably out perform the foam.
Your still might want to staple some grill fabric over the fiberglass just to keep the fibers from getting all over the place.
Felt is another option, but can be pricey, but works very well to tame vibrations, and absorb sound. The higher the wool content in the felt the better-F3 is pretty good stuff.
In fact, in my second set of AMT3's-I will be using felt on the rear baffles.
I'm using a fairly large custom crossover board, that's 3/4 thick wood, that will occupy a large section of the rear baffle. The felt, in addition to providing damping will also provide a seal/decoupling for the crossover board.
Then I will run four bolts and Hurricane nuts to firmly attach the board to the rear baffle.
Just bolting the board so far to the real baffle makes a huge difference in the resonating qualities of the AMT3 rear baffle. It's now a dull thud instead of a ring when your rap your knuckles on it. The addition of the felt should improve this.
That crossover board with the large inductors and other componets will add another 8 lbs of mass to the rear baffle, which should also aid in reducing vibrations.
In addtion, I'm using Ron's front baffle bracing technique, between the 2 woofer openings, and midway across the port section.

Artifact
12-15-2011, 05:14 PM
Since yours is a passive (vs ported) system, you could use fiberglass 'boards' or squares (basically compressed fiberglass) in your enclosure.
The fiberglass will probably out perform the foam.


Thanks for all the info automojo. I'll try to find the fiberglass boards. I too have been thinking fiberglass and partial filling with acoustistuff (trying to avoid blocking the passive radiator).
I'm currently working on installing new binding posts, sealing the cabinets, and repairing some chipboard damage done while removing the passive radiators (not sure why but removal of the PR's pulled away some approx. 1/8" deep chunks of chipboard). After doing some research on epoxy resin fillers and wood fillers have decided to go with "Famowood" wood filler. Apparently it doesn't crack and can handle drilling and screws. I will also be rewiring from the binding posts to the crossover and back down to the woofers. What guage do you recommend for this. I was thinking about 14 guage...
Your project on the AMT3s sounds really interesting. You should post something up - I'd be interested in seeing how it progresses.
Haven't received my resistors yet!
By the way, I notice that Solens carries the Swedish made Supra speaker cables - supposed to be very good. Have to check on shipping costs.

automojo
12-15-2011, 10:24 PM
The reason the chipboard stuck to the drivers was because ESS used the evil balck silicone to seal the drivers, instead of a gasket. P.E. speaker gasket works well, or you can just get some thin foam weather stripping and trim the width to size. It's much cleaner then caulk, and doesn't require too much effort on the mounting screws.
I will post some more info on the AMT3's when I get the chance to get more done. They should turn out pretty nice.
My first set sounds wonderfull with just a re-cap and rewire, along with the little stuff-sealing/mounting surface Hurricane nuts etc.
I will see with the Sonic Barrier on the second 'Super Set' and may add it to the first-along with the bracing.
The bass with the 1040SF's on the first set sounds very good-and it projects very well with out being boomy. Perhaps slightly colored-but it's very detailed and articulate- with out that 'snap' get from so called high resolution modern speakers, particuliarly poly woofers.
The one thing I really appreciate with the 1040SF's in my first set is the balance the bass has at low volumes with the AMT and midbass driver. You still get a satisfying bass response without having to fiddle with tone controls etc. All the other speakers I have had over the years never carried their balance into the lower volume levels. Bass would be thin, with the mids and highs dominating the frequency spectrum.
Usually I just lived with it, as loudness switches and bass controls can end up making the sound worse-boomy or weird phase shifts-so you live with the thinner sound.
With the original Alnico drivers the balance would come in at medium levels on up. The 1040's require, for the most part, the brightness switch to be set @ bright for the Heil to keep up.
They seem to take a good 15-20 hours or so to really break in, and the sound will change quite a bit in that time frame.
The nice thing about the AMT Heil-is that bright isn not 'bright' in terms of a horn driver or the like-just increased output with out the colored "shouting" of most horns.
I picked up a pair of Klipsch Quartet's (impulse buy)recently, and got to have some fun comparing the two.
The Quartet's have some pretty nice bass-but the 1040's AMT3's will easily keep up with them, with better detail. The Quartets, as my KG 5.5's have a very narrow sweet spot, where the AMT3's sweet spot is quite large-in fact they still sound very listenable basically facing one speaker-as you can still here 95% of the mids/highs from the distant speaker-not so with the Klipsch.
The AMT3's 'wall of sound'. With a good recording, the sound stage of the AMT3's usally extends in back of your head, probably about 30 degrees rearward or so from the tops of your ears-and imaging stays very stable. Pretty amazing IMHO.
And as other have mentioned, less colored overall then most Klipsch. It was a nice experiment-and I was able to move the QUartet's to a happy buyer with out a loss.

I will use the second 'super' set to evaluate any bass improvements-but will have to seperate it from the increased efficiency the second super set will have with the updated crossover.
With the 1040sf's 93 db efficiency, the AMT Heil in this configuration (and midbass driver for that matter) must be close to around that same 93db efficiency, gigven the balance and eveness of outputs from each driver.

ron-c
12-15-2011, 11:16 PM
Life is to short to use fiberglass in any speaker. As far as low volume listening to the AMT3s if your electronics are spot on they are superb at low volume. I would not say bigger amps are better but ESS was using their 500 watt amp when these were designed.

Thanks,
Ron-C

Boto
12-16-2011, 10:04 AM
The reason the chipboard stuck to the drivers was because ESS used the evil balck silicone to seal the drivers, instead of a gasket. P.E. speaker gasket works well, or you can just get some thin foam weather stripping and trim the width to size. It's much cleaner then caulk, and doesn't require too much effort on the mounting screws.


I am currently repairing a pair of the smaller PS-8's. They didn't use any sealant on the passive radiator at all. It looks like they expected the foam from from the radiator to seal it to the enclosure, since it was glued to the back of the frame.

Artifact
12-16-2011, 03:06 PM
Life is to short to use fiberglass in any speaker.
Thanks,
Ron-C

Although I don't think fiberglass is that bad, I'm also considering a relatively inexpensive felt type material as an enclosure damping material. It's available locally in Victoria from Planet_10 hi-fi. Info can be found at the following link: http://www.bondedlogic.com/oem-solutions/acoustical-solutions
Planet_10 claims that this is the best felt they have ever used in speaker cabinets. Works out to about $2.50 a square foot for 1/2" thickness.
Opinions appreciated!

Artifact
12-16-2011, 10:24 PM
I happened to be cruising the net today looking for local suppliers of audio and electronic goodies when I came across a rather negative, but probably quite true, statement about ESS crossovers on the Vancouver Audio Speaker Clinic:
"The success of ESS as a hi-fi speaker manufacturer during the 1980’s and 90’s was due to one overwhelming factor - the Heil air-motion transformer (AMT) tweeter that ESS licensed from inventor Oskar Heil. Sadly, the other components that went into ESS systems were not nearly as special as the lovely AMT. The most obvious flaw was their absolutely dreadful crossover networks, which were not only primitive in design, but also built with miserable grade components. Upgrading the crossovers involves more than the typical replacing of capacitors and inductors, because the fundamental design of the networks was rubbish.

Once equipped with proper crossovers, the AMT is less stressed, and the woofer sounds appreciably cleaner. Most of the ESS hi-fi enclosures are reasonably well made, and while it is possible to add bracing, the improvement is quite subtle. So, while the original woofers and passive radiators may need new foam edges, the cost is quite reasonable, and the results most satisfying."

I have followed up and very brazenly begged them to share their new crossover design. I'm not holding out much hope as they are in business, but it would be very interesting to see what they have.

automojo
12-16-2011, 10:30 PM
That insulation looks interesting, may be worth a try.
Nice thing if you don't like it- it's not hugely expensive.
I think with any of these modifications-you should try one speaker with it, and leave the other unchanged-and then make your decision.
As with any of these things, some is up to taste
I agree about the electronics/amps.
Once you get a good feel for what the AMT3 is, it really is IMHO fairly sensitive to the driving amps, in terms of getting the most out of it.
My two main amps-H/K PA2400 and H/K Sig 1.5 work very well-and each have the capabilty to drive them nicely at low volumes-the edge goes to the Signature.
Comparing the 1040 vs O.E. Alnico's-the 1040's seem to be at a more even output level to the other drivers, and this improves their low level performance vs the stock Alnicos-in balance over the frequency spectrumthe woofer is expected to operate.
Part of this may be that the magnet's may need a recharge, and at some point I will get mine recharged to give a more fair comparision-but as they stand-I think there is around 1.5-2db difference in the output of the 2 woofers.
So in this way they will change the voicing of the AMT3 over the stock woofers-and something you will either like, or not like.
In terms of artifacts, frequency emphasis, peaks valleys-the 1040 seems to be a very close match to the stock ESS woofer-which audibly seems to have a fairly flat response and smooth roll of charcterisitcs. Not a exact match, of course, but very similiar, with the exception of sensitivity and output.
I have a freind that has the P.E. Omnimic measuring system-so I plan on borrowing it and confirming what I hear-along with any differences in the frequency balance/peaks/artifacts etc over the Alnico and 1040SF.

Artifact
12-17-2011, 02:50 PM
That insulation looks interesting, may be worth a try.
Nice thing if you don't like it- it's not hugely expensive.
I think with any of these modifications-you should try one speaker with it, and leave the other unchanged-and then make your decision.
As with any of these things, some is up to taste

I hate to bring damping materials up again but the more I read about them the more I get confused. There is a lot of conflicting info out there. If I understand correctly, there are two types of damping: damping to decrease resonance in the cabinet walls (Sonic Barrier?) and damping to reduce the negative effects of sound waves bouncing around inside the cabinet. (Accoustistuff?). The top of the ESS AMT1b is constructed of butt jointed 3/8" chipboard with a major brace connecting the sides and top and two huge 12" holes covering most of the front and back panels. I assume that when the speaker and PR are installed in front and back they provide some rigidity, but not much. Given the rather flimsy construction of the top of cabinet, I assume the top of the cabinet is a good candidate for something like sonic barrier. The bottom half of the cabinet is 5/8" thick, seems fairly robust, and may not need resonance dampening materials. Also, the overall enclosure volume is quite large so I'm wondering if there is a need to increase the apparent volume of the cabinet by placing something like sonic barrier in the bottom half of the cabinet. The cabinet walls surrounding the woofer are lined with what looks like an artificial lamps wool and are ESS original equipment so would leave as is or replace with equivalent thickness of felt.
So basically what I'm thinking is possibly something like sonic barrier for the top of the cab and acoustistuff fill for the rest with provision to protect the PR from the fill (netting?).
Is this a totally wacko idea or am I somewhat on the right track? Sorry, I'm not sure anymore about my initial love for felt.

automojo
12-17-2011, 05:24 PM
The Sonic Barrier, unless it's the vinyl composte material is mainly made to absorb internal waves, although it will give you some cabinet wall damping, but that's not it's primary design goal.
Adding mass to the walls will deaden vibrations by changing the frequency, and the 'force' required to vibrate the walls.
ESS probably line the walls instead of filling it with the stuffing, like the AMT3 to provide the proper air movement to the passive radiator. Basically it's there to prevent the bare walls from reflecting soundwaves waves like a mirror. Personally I would keep what they have, it's fine.
You could address the rear panel by lining it with felt, and well as the front baffle, to add mass and absorb vibarations, and the bottom if it's thin. Your speakers design would require a novel approach to bracing. Adding another 'inner baffle wall to increase the thickness would reduce the internal volume, and require retuning-You probably could add some loose stuffing to make up for this-but it seems like a whole can of worms to open up with out having a 'base' reference to go on-how the speaker will sound with the new crossovers, new drivers-sealed cabinets and stock damping material.
You may be perfectly happy.
After you have heard them, and want to try to improve any colorations etc:
Since your speakers aren't 'stuffed' like the AMT3's, any bare surface would do well by being line to slow down/and absorb refections.
The thought with increasing the apparent volume is that many times a slight increase will allow the woofer to operate more effectively. This usally works with many speakers.
The reason foam, and poly stuffing (fiberous material) increase the apparent volume is that they cause air friction-rasing the internal temprature of the enclosure-thus making the air less dense and 'fool' the speaker it's dealing with more volume.
This being said felt and the like don't reflect soundwaves back like foam and poly, nor do soundwaves pass through them (very well) like foam and poly. So they absorb sound waves (for the most part) and reduce vibrations by adding mass.
Composite material, like the 3part Sonic Barrier doesn't pass sound waves either- is it has a sheet of vinyl. The single type foam Sonic Barrier will pass some sound waves-high/mids/some midbass will be absorbed, but not any bass waves etc.
By stuffing the speaker on the AMT3, ESS has addressed 2 things, increased the apparent volume, and the slowing down, or filtering of soundwave reflections in the cabinet. The stuffing does help some with vibrations by merly slowing down and 'redirecting' the soundwaves. What it doesn't deal with is vibrations caused by large bass waves, as these require thick dense stuffing. But this should't be a probelm here.
The main reason to address the front and back baffles is because the deal directly with the driver, or it's back waves, and in your case the PR.
Beyond possible putting some felt on the inner baffle surfaces, I would probably leave it as is-and just address any large areas that aren't covered by the stock stuffing. The stock stuffing is taking care of the reflections of the bare walls for the most part, and if they are as thick as the AMT3 side walls-with the exception of tightening the 2pc walls- they are plenty thick and damping them to reduce vibrations (as opposed to preventing them from reflecting) probably wouldn't yeild much of a difference.
What you don't want to do is over damp the enclosure and change the tuning and affect the bass in a negative way.
So in a nutsheell, I would take the minimal approach. Seal and glue the cabinet, (and probably just go ahead and add some damping to the bottom panels if it's bare) get your crossovers done/rewired and install them with your new drivers/Pr's and give them a listen.
Then go from there.
My problem is that doing too much with out a reference to go on-you may end up doing too much, and wasing money on materials you don't really need to achieve your goals.

automojo
12-18-2011, 06:55 PM
Missed the Vancouver thread- I agree they used fairly inexpensive caps (they were not the only ones at the time either- but for their day-the air coil inductors are better then alot of new speakers.
The crossovers PC boards in the AMT3 are of good quality, and besides the caps-it's all looks anyway. Plus where dealing with in some cases almost 40 year old speakers-and just by the nature of their design-they will need some work.
It's really hard to compare a old unrefurbished speaker to modern ones. It's funny how people still want to make this unfair comparison-is it makes little sense.
Caps have come along way since those days- as well as thoughts on speaker design-but I don't think ESS was that far off IMHO on most models- and with the AMT3-they got it right.
A refurbed AMT3 will give most modern speakers a serious run for the money-along with many other of the Great Heil/AMT models with the right driving and source equipment.
I can't imagine Vancover Speaker changed much as far as crossovers points, as changing them using the stock drivers probably wouldn't improve much, as I think ESS understood where they need to corssover the drive units-the main problem they dealt with was getting the AMT Heil to match up with a 10-12" woofer.
The smaller 8" units didn;t really have this problem-but then of course wouldn;t have large bass output.
The 3 way designs for the most part solved this problem (AMT3/PS 1220).
As far as bracing-I'm not sure-I know the did some of this with one or 2 AMT Monitor models- so obviously they thought it was a problem.
There is a thread-have to find it, were a audio pecialty place took a AMT3 cabinet and added a second inner wall to the front and back panels-used a single (12" I think) high output Gauss woofer, along with a transition driver- topped off with the AMT. The owner described it as one of the most dynamic speakers he had ever heard.
Some manufactors used cabinet colorations as part of their sound-Paul Klipsch liked the sound of plywood- but most don't.
Sometims the colorations aren't all that bad, or can be favorable to some listeners.
I just posted some pics on bracing my AMT3 between the woofer opening.
http://www.audiokarma.org/forums/showthread.php?p=5235789#post5235789
This worked out very well-the front baffle is very solid now with a dull thud instead of a ring when you rap your knuckles on it. How this translates in the sound remains to be heard. I would guess it should help.
It can't hurt, and in reality it's not all that difficult to do with a few basic wood working tools and $20 worth of materials-wood-screws and epoxy(epoxy being the most expensive componet).
IMHO the basic design of the AMT3 and most AMT speakers is fine- they just need the right amount of updating.

mrappe
12-18-2011, 07:27 PM
I am thinking of re-capping my AMT1Bs also. Please let me know what you go with and how it turns out. Most of the discussion about caps is over my head but i know how to solder.

Thanks

Artifact
12-18-2011, 09:53 PM
I am thinking of re-capping my AMT1Bs also. Please let me know what you go with and how it turns out. Most of the discussion about caps is over my head but i know how to solder.

Thanks
After reading a lot of reviews I went with 250V Mundorf M-Cap MPK capacitors, 2 X 33uf and 2 X 10uf and 1 X Mills resistors 3.9 ohm 12 Watt for each speaker. These aren't the ultimate caps you can buy but you are getting very esoteric and very expensive after their price point (about $65 for each speaker including shipping and tax) Parts Connexion (Canada) and Madisound US) has them. The caps are used by quite a few excellent speaker companies, Sonus-Faber among others. Another reason I bought them is they can fit on the existing circuit board without having to move or reorganize other components. Many of the good caps today are HUGE.
It's going to take me quite awhile to finish the complete refurb of my AMT1b's so I can't comment on the sound as yet. I'm sure it will be an awesome upgrade!
Cheers!

Artifact
12-18-2011, 10:11 PM
A refurbed AMT3 will give most modern speakers a serious run for the money-along with many other of the Great Heil/AMT models with the right driving and source equipment.

I know what you mean, I was seriously looking at some Totem Rainmakers a couple of months ago and in fact took my wife in to audition them for a second time. They were very nice, but then my wife posed the question "Well, what would you rather have the ESS or the Rainmaker?" Not hesitating for a second, I immediately replied "The AMT1b's" It seems every equipment upgrade I have made in my system has improved the sound. I still feel there is plenty of room for improvement. I would like to add better amplification, a new CD player, and possibly a DAC, but it won't happen soon unless I win the lottery!

Artifact
12-19-2011, 11:19 AM
The main reason to address the front and back baffles is because the deal directly with the driver, or it's back waves, and in your case the PR.
Beyond possible putting some felt on the inner baffle surfaces, I would probably leave it as is-and just address any large areas that aren't covered by the stock stuffing. The stock stuffing is taking care of the reflections of the bare walls for the most part, and if they are as thick as the AMT3 side walls-with the exception of tightening the 2pc walls- they are plenty thick and damping them to reduce vibrations (as opposed to preventing them from reflecting) probably wouldn't yeild much of a difference.
What you don't want to do is over damp the enclosure and change the tuning and affect the bass in a negative way.
So in a nutsheell, I would take the minimal approach. Seal and glue the cabinet, (and probably just go ahead and add some damping to the bottom panels if it's bare) get your crossovers done/rewired and install them with your new drivers/Pr's and give them a listen.
Then go from there.
My problem is that doing too much with out a reference to go on-you may end up doing too much, and wasing money on materials you don't really need to achieve your goals.

I'll be picking up my felt this week from David Dlugos at Planet_10 HiFi. He appears to have had quite a bit of experience with rebuilding ESS products as can be seen below. Hoping to get some additional ideas from him about damping etc.

http://homepage.mac.com/tlinespeakers/FAL/images/heil_3way.jpg

http://homepage.mac.com/tlinespeakers/FAL/box-plans/heil-fostex.jpg

automojo
12-19-2011, 02:27 PM
I'll be picking up my felt this week from David Dlugos at Planet_10 HiFi. He appears to have had quite a bit of experience with rebuilding ESS products as can be seen below. Hoping to get some additional ideas from him about damping etc.

http://homepage.mac.com/tlinespeakers/FAL/images/heil_3way.jpg

http://homepage.mac.com/tlinespeakers/FAL/box-plans/heil-fostex.jpg

Interesting 3 way design-looks like a Eminence Alpha 6A for the mid driver.
I think some of the damping is a hit and miss type of thing as far as improvements go.
A good reason to use the Hurricane nuts and speaker gasketing material as it makes it a snap to pull the drivers, and won't wear out the holes in the baffle.

automojo
12-19-2011, 11:37 PM
Amazon is also a excellent source for felt-I picked up some f-13 12x12 square for 2.16 ea. Doesn't have adhesive, but I have plenty, plus a staple gun.
I plan on lining mainly the woofer 'compartment'-2 squares on each side-one for the bottom, and 2 for the back as mention. I will also apply some to the brace, as it's in very close proximity to each woofer.
Interesting comparison on the Totems.
Nice choice on caps- they should work just fine.
The ESS AMT's are like any high end speaker, and really require proper amp matching to maximize their performance. But they really can compete with many current manufacturer's , and truly hold their own. Really amazing considering their age. The AMT's are truly well worth the refurb effort.
They aren't a low, or mid resolution speaker you can just plug and play.
I see this all the time-people trashing products, not because they are bad, but because they don't realize you can't just plug and play certain components.
I used to love Stereo Review, the only problem I had with them, was that they many times, inaccurately,carried on the belief that most stereo components are, and should be plug and play.
They have been gone since the 90's- but this belief still seems to have life- as I see threads each day that more or less assume this.
Some components you have to be willing to go a little further to reach maximum results- if you aren't- stick with midfi- you will be much happier

mrappe
12-20-2011, 09:03 PM
After reading a lot of reviews I went with 250V Mundorf M-Cap MPK capacitors, 2 X 33uf and 2 X 10uf and 1 X Mills resistors 3.9 ohm 12 Watt for each speaker. These aren't the ultimate caps you can buy but you are getting very esoteric and very expensive after their price point (about $65 for each speaker including shipping and tax) Parts Connexion (Canada) and Madisound US) has them. The caps are used by quite a few excellent speaker companies, Sonus-Faber among others. Another reason I bought them is they can fit on the existing circuit board without having to move or reorganize other components. Many of the good caps today are HUGE.
It's going to take me quite awhile to finish the complete refurb of my AMT1b's so I can't comment on the sound as yet. I'm sure it will be an awesome upgrade!
Cheers!

I looked at my crossovers and I found this:
75 V 33 mfd
2 x 100V uF 10 (NP)
50V 33 uF (K)

I am not shure what the (K) refers to

Did you get all of your caps from the same place?

http://i1202.photobucket.com/albums/bb376/mdrappe51/essamt1bcrossover.jpg

automojo
12-20-2011, 11:34 PM
Parts Express, Erse Audio, Madisound, Meniscus Audio are all good source for caps.
Mimimum of 100 volts for each capp, but usually polys are at least 200 volt.
Mundorf are fine- Erse PulseX, Solen Dayton polys are really all fine. Tight tolerences are what's important. ESS used 10% caps, but they will really benefit from 5% or less.
IMHO you won't really hear a difference between the caps-and you really shouldn't becasue a caps job isn't to sound like something-just store and pass the signal-alot of guy's get hung up on crossover caps needlessly.
What you will hear is the difference between out of specs caps vs new ones- that's were the real change is, and this change is mistaken for cap type brand etc.
The 33's would be fairly large with most poly's but you should have enough room.
The Erse Pulse X 250 volts are typically shorter then many other polys'- Solens as well- the Daytons are pretty big and long-but as long as you have enough room-or just add a small cabinet 'pad'-you should be fine.
Polys caps have a longer life then electrolytics, and in general lower esr-but many modern electrolytic have fairly low esr as well-compared to caps of 30 years ago.
Given that- polys once installed won't have to be changed in your lifetime, unless you have a amp go dc etc, so the few extra dollars for Daytons or the like isn't that big of deal.
Personally I would spend the time and money resealing the cap, proper damping where applicable, and save your money for a few new lp's or cd's to listen on your newly refurbished speakers.
Having said that, if the more expensive poly's make you fill better about your overhaul- by all means indulge.
I would also replace that 4 ohm resistor as well-Dayton's or Mills are fine.

mrappe
12-21-2011, 03:25 PM
I don't want to have to add any extra space to the board. I would like to see what Artifact will have done. I am not sure what "esr" is. The speaker has damping. I am not sure where i can add any that would not get in the way the way of the PR. Also,
I am not sure what you mean by 'resealing the cap'. The cabinet is fairly tight from what i have see except the small hole that the wires up to the Heil run.

Thanks for the info

automojo
12-21-2011, 03:32 PM
I don't want to have to add any extra space to the board. I would like to see what Artifact will have done. I am not sure what "esr" is. The speaker has damping. I am not sure where i can add any that would not get in the way the way of the PR. Also,
I am not sure what you mean by 'resealing the cap'. The cabinet is fairly tight from what i have see except the small hole that the wires up to the Heil run.

Thanks for the info

Resealing the cabinet. They may look solid-but the probably have some air leaks-small ones make a big difference in how the woofer and bass perform.
Run some epoxy on all the interior seams-and silicone on top to make sure you have a good seal.
Painting the outside black surfaces is also a good thing-seals and stabilizes the old MDF.
Also apply expoxy to the woofer and PR baffle mounting surfaces to prevent chipping, and use Hurrican nuts and gasket tape.
If you do a serach of my threads a lot of this info is available.

Boto
12-21-2011, 05:52 PM
Resealing the cabinet. They may look solid-but the probably have some air leaks-small ones make a big difference in how the woofer and bass perform.

Painting the outside black surfaces is also a good thing-seals and stabilizes the old MDF.


I just redid a different model of ESS but they were from the same era and the crossover was made on the same material. It was masonite, not MDF. I'm not sure that it wouldn't leak a bit through that cheap material after all these years. I made a new one out of MDF to replace it.

Artifact
12-21-2011, 09:22 PM
I looked at my crossovers and I found this:
75 V 33 mfd
2 x 100V uF 10 (NP)
50V 33 uF (K)

I am not shure what the (K) refers to

Did you get all of your caps from the same place?

http://i1202.photobucket.com/albums/bb376/mdrappe51/essamt1bcrossover.jpg

Hi mrappe, the values of your individual capacitors are identical to mine. The voltage of the originals is not all that relevant, in fact it is better to go for a higher voltage (250V or 430V). The important value is the uf and also the tolerance (less than 5% or less is good) In your photo it looks as though one of the original L-Pads has been replaced by a smaller one or maybe it is from a different year of production than mine(1979). See photo below. Note: two of my caps are stacked one on top of the other at the top of the board. I did buy all my caps and resistors at Parts Connextion in Ontario. They are good to deal with and if you want to ask any questions you can phone them toll free. I have attached another photo showing how I plan to place the new caps (click images to expand). PS: I discovered yesterday that my "Mundorf" MKP caps are probably rebranded Solen "Fastcaps"..... If I had the money and the space on the board I would probably buy ClarityCap ESA 250V or ClarityCap SA 250V. I used the SA model in a recap of EPI 100's and the difference was very significant..
318527

318528

automojo
12-22-2011, 08:44 AM
I just redid a different model of ESS but they were from the same era and the crossover was made on the same material. It was masonite, not MDF. I'm not sure that it wouldn't leak a bit through that cheap material after all these years. I made a new one out of MDF to replace it.

I'm sure the sealing of the masonite board as pictured, or MDF board would be fine. As far as sealing, I was talking about the internal seams.
Most cabinet and/or furniture makers use a minimum of glue for economic reasons, and for the plain fact it won't leak out of the seams and become visable.
Sealing the drivers/PSR is also important.
Age is also factor, as things dry up and shrink, and gaps and leaks develope.
MDF is basically saw dust glued together under pressure. It can have some stability problems over the years-especially in damp enviroments. That's why I suggested painting the outside black surfaces, and sealing the seams, and dealing with the driver mounting surfaces.
Just by sealing my AMT3 cabs, the bass cleaned up noticeably-well worth the effort IMHO.
All the caps mentioned are fine-seriously you would be hard pressed to tell the difference between any of the good caps, even electrolytics, in my experience with AMT's-the tolorence is the big issue.
Reducing the ESR makes the speaker more efficient, and a easier drive for amplifiers. A lower ESR may be audible with some amp setups, not because of the type of cap, but the ESR rating.
Basically you are taking advantage of technology improvements, at a fairly reasonable cost IMHO.

mrappe
12-22-2011, 05:02 PM
I used the SA model in a recap of EPI 100's and the difference was very significant..



I always loved the EPI 100s. My good friend got some in 1972 and ever since I wanted to get a pair of those.

mrappe
12-22-2011, 05:08 PM
Painting the outside black surfaces is also a good thing-seals and stabilizes the old MDF.


I have been wanting to re paint the black areas for several years and have been putting it off because I wanted to make sure that it looks as original as possible. Any suggestions as to which paint and method to use?

automojo
12-22-2011, 05:45 PM
I have been wanting to re paint the black areas for several years and have been putting it off because I wanted to make sure that it looks as original as possible. Any suggestions as to which paint and method to use?

Most were a satin black-some semigloss. And some may have been repainted by the previuos owners. I used a flat black-followed by a satin clear-both from Krylon. Looks great and doesn;t to the finger print thing.

Artifact
12-24-2011, 04:54 PM
The rheostats can make up for it

I'm planning on replacing the L-Pads (rheostats) on my AMT1b's since I recall that they were a little "scratchy" sounding when I last had them up and running. There are two L-Pads in each speaker, one that controls "Brilliance" on the Heil, the other controls "Midrange Resence" on the Heil. Would these be Mono L-Pads or Stereo L-Pads? I'm a bit confused as I haven't seen any schematics showing 2 L-Pads controlling different frequencies on the same speaker. I'm also having difficulty finding L-Pads that are the same diameter or length/width as the originals (1 1/2" diameter with a 3/4" stem) Most of them are a larger L/W. This makes it difficult to wire them as they are too close together. I thought I may be able to get around this by installing one with a 1" stem and the other with a 3/8" stem, i.e the 1" stemmed one could be adjusted to tower over the 3/8" to allow wiring. If anyone has replaced their L-Pads on an ESS AMT1b it would be appreciated if you could let me know what you used. Thanks!

Pandovski
12-24-2011, 05:07 PM
I would just fix the woofer by gluing with a patch in the backside. Since I've done this before I am sure if the job is done right there should be no audible difference between the 2 woofers. Use a patch with same material as the woofer cone, or similar. Do not use fast drying glues, just the quality typical universal glue.

If you don't like it you can always buy a different woofer. Fixing is free.

Artifact
12-25-2011, 11:40 AM
I'm planning on replacing the L-Pads (rheostats) on my AMT1b's since I recall that they were a little "scratchy" sounding when I last had them up and running. There are two L-Pads in each speaker, one that controls "Brilliance" on the Heil, the other controls "Midrange Resence" on the Heil. Would these be Mono L-Pads or Stereo L-Pads?

I'll answer my own question. Don't know how I missed it but Stereo L-Pads have 6 terminals and one pad could individually control the woofer, midrange, and tweeter in the same speaker, mine have 3 terminals so they must be Mono.

mrappe
12-25-2011, 11:57 AM
I'm planning on replacing the L-Pads (rheostats) on my AMT1b's since I recall that they were a little "scratchy" sounding when I last had them up and running.


Have you tried cleaning them out with FaderLube? I think that it is safe for those from what I have heared.

mrappe
12-26-2011, 01:33 PM
Also apply expoxy to the woofer and PR baffle mounting surfaces to prevent chipping, and use Hurrican nuts and gasket tape.

On the PE website I found these nuts:

http://www.parts-express.com/pe/pshowdetl.cfm?&Partnumber=081-1080&scqty=1

I assume that this is what you are talking about.

Artifact
12-26-2011, 04:22 PM
Have you tried cleaning them out with FaderLube? I think that it is safe for those from what I have heared.

I'm going to look for Faderlube locally as shipping is so costly. For example, it will cost more to ship the L-Pads I want than their retail price...

mrappe
12-26-2011, 10:43 PM
One of my lpads has a static sound when turning it so i was going to try cleaning it with the faderlube.

Artifact
12-27-2011, 12:47 AM
One of my lpads has a static sound when turning it so i was going to try cleaning it with the faderlube.

Let me know if it works, I would much prefer to go this route rather than buying new ones, although in my case the L-Pads are 32 years old and maybe there's not much hope for them! Was it one of the original L-pads that was causing the problem?

diamondsouled
12-27-2011, 02:10 PM
I spoke with Ricky Caudillo, the CEO at ESS yesterday. Reconing the existing woofers is $100 each plus shipping to ESS and shipping back to me again. Have therefor decided to get the new treated paper woofers at $140 each plus shipping. I may also go for new Heil diaphragms at $80 each although Ricky stated that if the wiring in the existing diaphragms seems "straight" (in vertical alignment?) I shouldn't need them. However, reviews of the replacement diaphragms on Parts Express seem to indicate that replacements make a huge difference in sound...
Next step is figuring out what caps I need for the crossovers. Being a relative newbee I'm trying to research info on series vs parallel configurations and things like bypass and cascading capacitor configurations. "diamondsouled" did his crossovers recently but I don't quite get what he has done. Has he simply piggy backed and joined the wires of the new caps to make up the original capacitance? (Yes this stuff is well over my head, but I do have lots of time...) See below:
http://mail.audiokarma.org/forums/attachment.php?attachmentid=132106&d=1233123248

Those crossovers actually ended up sounding excellent :yes:

Making up capacitance values by paralleling is also known as cascading. Good article on that here:

http://www.northcreekmusic.com/Bypassing.html

Artifact
12-27-2011, 04:51 PM
Those crossovers actually ended up sounding excellent :yes:

Making up capacitance values by paralleling is also known as cascading. Good article on that here:

http://www.northcreekmusic.com/Bypassing.html

Thanks for the info. I have thought about paralleling on a small value higher end cap to each of the 33uf and 10uf Mundorf MPKs (apparently Solen Fastcaps) I bought. Thinking about ClarityCap ESA but am also thinking I have spent enough money already....

Boto
12-27-2011, 07:47 PM
I'm sure the sealing of the masonite board as pictured, or MDF board would be fine. As far as sealing, I was talking about the internal seams.

Sealing the drivers/PSR is also important.
Age is also factor, as things dry up and shrink, and gaps and leaks develope.
MDF is basically saw dust glued together under pressure. It can have some stability problems over the years-especially in damp enviroments. That's why I suggested painting the outside black surfaces, and sealing the seams, and dealing with the driver mounting surfaces.
Just by sealing my AMT3 cabs, the bass cleaned up noticeably-well worth the effort IMHO.



I whole heartedly agree with you on sealing the cabinets better. There were no obvious seals on any of the drivers of my PS-8's. I added a sealant (rope caulk) to everything and they sound much better on the low end.

My worry on the masonite board was due to how it was made. Masonite is made in a steam and pressure environment: there are no resins (glues) used in the boards. My fear is that over the years of aging that the masonite would have a tendancy to "breathe" right through the material itself, and no amount of paint would properly seal that panel. For the few $$ it would cost to make a new one, I would make one out of masonite or MDF. Cheap insurance for another 35 years of good sound from the speakers. :music:

automojo
12-27-2011, 10:47 PM
On the PE website I found these nuts:

http://www.parts-express.com/pe/pshowdetl.cfm?&Partnumber=081-1080&scqty=1

I assume that this is what you are talking about.

Yes-they are small enough to fit-just make sure you glue them as well with epoxy.

automojo
12-27-2011, 10:53 PM
One of my lpads has a static sound when turning it so i was going to try cleaning it with the faderlube.

These are fairly good quality, and should clean up with fader lube. However-if you want to go all out- new ones aren't that expensive.
I would test them out after cleaning on a test full range speaker (not the Heil-to make sure they are working.
Many time a few quick back and forth motions with the knob will clean them.
Sometimes, however they do get a 'dead' spot if they wern't moved much- right in the position they were left-but unless they had bad plating, or were in a humid enviroment-they are probably fine.

mrappe
12-29-2011, 09:19 PM
This is the stuffing in my ESS AMT1Bs I would think that having it come all the way up in the speaker would hinder the PR.

http://i1202.photobucket.com/albums/bb376/mdrappe51/amt1binterior2.jpg

http://i1202.photobucket.com/albums/bb376/mdrappe51/amt1binterior1.jpg

Artifact
01-01-2012, 02:45 PM
This is the stuffing in my ESS AMT1Bs I would think that having it come all the way up in the speaker would hinder the PR.

Yes, I think the way the back of the cabinet is stuffed would probably hinder the movement of the passive radiator, although I'm also wondering if ESS intended the polyester fibre to somewhat dampen the movement of the PR. However, I would be surprised if the latter were true. As indicated earlier in the thread I think I might test by placing some netting between the PR and polyester to prevent any interaction.

automojo
01-01-2012, 10:37 PM
You could try it both ways-the poly stuffing really is 'invisable'to bass waves to a point-it may provide some needed damping Stuffing is mainly is to control midbass/midrange staning waves-and to slow down/eliminate reflections. It alos may be need for the correct box tuning- so I wouldn't change the amount that ESS put in there-unless you go up slightly.
The AMT3's are stuffed to the gills-but I have never heard, or noticed any cone movement problems-as the stuff is fairly light weight.
It's possible ESS used this-as in the AMT3's (most are ported)as-as mentioned- a resistive stuffing, or loading of the enclosure to clean up any woofer doubling effects and more closely tune the enclosure.
You have to remeber-speaker tuning etc was a inexact science-that's why in part you have mid/high frequency l-pads.
Usually ESS seems to have the tuning etc fairly close-with a few small adjustments only needed-sealing and strengthening the cabinet-along with pulling apart and evenly distributing the stuffing will give you the most noticable improvements.
I recently followed RonC's recommendation about pulling out the stuffing-pulling it all apart-and evenly distributing it in the cabinet. This really makes a big difference- at least in the AMT3's. The sealing also made a huge difference.
ALL the ESS AMT's are highly revealing speakers-and sensitive to changes-good or bad, especially magnified when the woofer has to deal with the speed and efficiency of the Heil.

mrappe
01-05-2012, 12:03 PM
I just ordered the new Caps for these. I picked the same ones that Artifact ordered and Parts Connexion came back and said that they were out of the
10uf / 250V, M-CAP® MKP Series, 24*33mm
so I ordered the
10uf / 400V, M-CAP® MKP Series, 26*39mm
I know the 400V is a little larger physically but it should be electronically OK to use these instead of the 250V ones right?

IBJamon
01-05-2012, 01:18 PM
Yes they will work just fine. Some suggest higher voltage caps sound better, though I am not aware of much science to back that up.

IBJamon

mrappe
01-05-2012, 03:34 PM
Thanks for the response

Artifact
01-11-2012, 03:49 PM
Finally finished the first crossover as shown below. To summarize:
Original caps replaced with Mundorf M-Cap MKP Caps (33uf and 10uf 250V)
Original resistors replaced with Mills MRA-12 3.9 ohm Resistors
L-Pads replaced with Yung LP50 1" shaft 50W (same as Fostex)
Some of the soldering is a little crude - first time soldering!

Other completed tasks include:
Replace binding posts with Dayton Audio*BPFI-G (appear to be made by WBT)
Redo much of the internal wiring with used Audioquest 16AWG speaker cable
Refurb speaker covers
Install 1/2 felt in bottom of speaker cabs and back panel of top cabinet. Will use original polyester fill as well.
Re-glued and sealed all speaker seams
Repaired damage to passive radiator cut-outs
Refoamed passive radiators
Repainted cabinets

Seems to have taken forever but had fun and learned a lot doing it! More photos and updates to come.

sti2k5
01-11-2012, 04:37 PM
Great pic...I'm gonna have to re-do mine...and I'll take all this advice and get it done! I was contemplating just doing a whole new board too...what website did you get all this from again?

I have a set of 1Cs that need done.

Artifact
01-11-2012, 09:10 PM
Great pic...I'm gonna have to re-do mine...and I'll take all this advice and get it done! I was contemplating just doing a whole new board too...what website did you get all this from again?

I have a set of 1Cs that need done.

I bought the caps and resistors at http://www.partsconnexion.com/ and the rest of the parts from http://www.parts-express.com/
http://www.madisoundspeakerstore.com/ has the same or similar parts as well.
Best of luck on your project!

mrappe
01-13-2012, 04:33 PM
I just got my caps yesterday. They were out of the 250V 33mfd ones so I got the 400V ones. I am trying to determine how to fit it all on the board. Thank you for the picture. It looks good. I was thinking that maybe i could save room if I mount the new caps so that the ends are vertical.

Artifact
01-13-2012, 04:52 PM
I just got my caps yesterday. They were out of the 250V 33mfd ones so I got the 400V ones. I am trying to determine how to fit it all on the board. Thank you for the picture. It looks good. I was thinking that maybe i could save room if I mount the new caps so that the ends are vertical.

My new board is very cramped with the new l-pads and just the 250V caps. I had to move one inductor on each crossover to cram everything in. Although it would be a big job, you might want to think about installing a new larger board to cope with the space issues. There is about another 6" of space in the top of the cabinet. I wish I had done this to make wiring easier and to allow for somewhat better (and bigger) caps. Another alternative would be to make space for the 400V caps, then stack the 250V ones on top. Vertical mounting seems possible. How were you planning on mounting them and still being able to wire both ends of the cap easily?

mrappe
01-13-2012, 06:26 PM
I will have to look at the board and compare it to your pic. I was meaning to ask you what gague of wire you used. It looks pretty stout. Also, I did not order new Lpads so If i decide to get some, where did you get them? I may put a larger board under the existing board that would give more space.

Artifact
01-13-2012, 10:30 PM
I used 16 gauge wire but the insulation was very thick - a bit difficult to work with because it doesn't bend well. The cap leads are 18 gauge so I thought I would go a little larger. The L-Pads I bought are quite large (2X2 inches) but they were the only decent ones that fit the bill. Note that I changed the facing of the terminals because they fit too close together to wire them the same as the originals. This means of course that the existing adjustment markers on the outside of the cabinet won't indicate the same adjustment as with the old L-Pads. However, it's pretty easy to figure it out by fiddling a bit with the new L-Pad, determining where center adjustment is and then fitting the old adjuster nobs to align with your determination of center when you first install them. I bought the L-Pads at http://www.parts-express.com/pe/showdetl.cfm?Partnumber=260-255

Artifact
01-13-2012, 10:47 PM
PS: If your original crossovers are the same as mine, the layout is not the same on both boards - not even remotely. You'd think they would have used a template....
I initially assumed that both boards would be pretty much identical and had a bit of a surprise when I found this was not the case.

mrappe
01-13-2012, 11:43 PM
I have only one speaker's board out and I am going to do it first to compare the sound with the other. From looking at mine and your new arrangement it seems like you may have moved the lower right choke up a little to make room for the cap and moved the large choke on the left down to the middle. How did you get them loose?

automojo
01-14-2012, 12:24 AM
Nice job!
You can use a razor balde to cut the glue, or judicious use of a heat gun-and hot glue or silicone to reattach them.
You should also be able to use a new larger board to incorporate the larger componets.
I don't think I would stack the caps vertically- you want them attached well, and not have such a sharp bend in the leads. You can strap one cap on top of the other to save room. Use a nylon tie, with either a little glue or silicone between the cap bodies. Parts Express has nice nylon ties that have a boss for a screw to attach them.
I built a larger board for my second set of AMT3's to incorporate the larger coils and caps. I used a 3/8' board-as this/ along with the large sides of the board will help thicken the rear panel. I will also use felt on the back side-which will also be the sealing gasket, instead of silicone-between the coroover board and back panel.
You could also run a smaller second board for the caps, and run wires to the main crossover board-but I would keep the distance-i.e. attaching wires to a minimum.

Artifact
01-14-2012, 11:59 AM
From looking at mine and your new arrangement it seems like you may have moved the lower right choke up a little to make room for the cap and moved the large choke on the left down to the middle. How did you get them loose?

On the crossover shown in the photo, only the leftmost choke was moved to a more central/left location to enable installation of both 33uf caps. On my second board, I had to move the smallest choke on the lower right to a position identical to that on the first crossover. To loosen the chokes I used a brief blast from a heat gun and a small putty knife. A hair dryer would also work fine.

mrappe
01-15-2012, 05:13 PM
I finished one crossover. I cut another board out of hardwood that is a little bigger to add some room and glued them together with siliconed and added some cork & rubber gasket material to the back. It is not pretty but hopefully it will work. I made some of the 16ga leads a little too long because I will probably replace the lpads before too long.

http://i1202.photobucket.com/albums/bb376/mdrappe51/Xover__20120115_050147_0018.jpg

http://i1202.photobucket.com/albums/bb376/mdrappe51/Xover__20120115_050209_0020.jpg

automojo
01-15-2012, 09:16 PM
Very nice work as well!:thmbsp:
I like the improvising with materials you had-and the cork gasketing material is a nice touch, and will allow easy removal if you choose in the future. Also the shrink tubing is a nice touch-which I'm also doing on mine.
I ended up with a large board in part because I wanted plenty of rome to lay things out, and it ened up having the added bonus to strengthen the rear panel becasue of it's size. Kind of fell into this one.
I did have to trim the top a bit because it was touching the mid tube, and I had already cut out the space for the brightness switch.
I'm sure those will sound excellent-and looking foward to your thoughts after the refrub.
It's amazing how well the AMT's respond positively to a few basic tweeks and upgrades.
Something to consider if your dealing with a basic stock set-your missing moving them up to the next level.
I appreciate all the great info and pics-very nice reading and enjoying!:thmbsp::music:
Thanks!

Artifact
01-15-2012, 11:47 PM
I finished one crossover. I cut another board out of hardwood that is a little bigger to add some room and glued them together with siliconed and added some cork & rubber gasket material to the back. It is not pretty but hopefully it will work. I made some of the 16ga leads a little too long because I will probably replace the lpads before too long.


Awesome! It will be great to compare notes on sound once we have our speakers up and running. I have both crossovers installed now and am in the process of finishing off the felt damping material.

Artifact
01-16-2012, 10:57 AM
I finished one crossover.

Just thought I would advise that the cabinet hole for the leads from the crossover to the AMT is not sealed on my speakers. May not be on yours either. I sealed mine from the inside with a silicone based sealant last night. Surprised my speakers weren't whistling like a tea kettle!

mrappe
01-16-2012, 12:58 PM
I knew that mine was not sealed either. i was planning on doing the same thing. Also, the place wher the wires go out to the binding posts on the bottom. What kind of felt are you using and where?

Artifact
01-16-2012, 02:07 PM
I'm using 1/2" "felt" from http://www.bondedlogic.com/oem-solutions/acoustical-solutions I managed to get it locally in Victoria BC. I have covered everything in the lower part of the cabinet and also on the back panel around the passive radiator and adjoining walls behind the brace. I may put some in the area surrounding the speaker to supplement the old fake wool damping, which has seen better days. I won't be putting any felt on the brace other than what is already there on the speaker side. I will also tease out the existing polyester fill and reinstall it.

sti2k5
01-16-2012, 03:42 PM
I just put my 1C's into paint today...then I need to go and seal the insides...not sure about re-doing the crossovers...still up in the air about it, but I think it would give me practice for a tube amp I want to build...

Glad to see more folks working on these!

djnagle
01-16-2012, 04:45 PM
Hi Sti2k5, I would at the very least replace the caps. The coils and resistors (if they still measure right) should be OK, but caps go with time.

Artifact
01-16-2012, 04:51 PM
I just put my 1C's into paint today...then I need to go and seal the insides...not sure about re-doing the crossovers...still up in the air about it, but I think it would give me practice for a tube amp I want to build...

From what people have said in the speaker forum, re-doing the crossovers is well worth it. My rebuild started with the idea of just doing the crossovers but soon escalated to a totally nutsoid megaproject. I should know in about 3 or 4 days if it has all been worth it! All the best on whatever you decide to do.

mrappe
01-16-2012, 07:39 PM
ON my 1Bs I was listening to them carefully a few weeks ago before starting on one speaker and I noticed that one speaker sounded slightly better than the other. I was not sure weather it was the diaphram or not. One sounder a little more airy and open. Then I started to work on one speaker because I wanted to see wanted to keep one working to listen to and so I could compare the re-capped speaker to the other. So I started with the one that sounded slightly duller than the other. I am almost ready to put it back together and I decided to open up the other speaker yesterday to look at the crossover and to my surprise I found that one of the caps on the board was bad and while it was left in place it had been replace with a newer one. This was probably done when the surrounds were replaced sometime before I bought it about 8 years ago. I wonder if that is why that speaker sounds better? anyway I am anxious to see how the reworked one now sounds.

mrappe
01-16-2012, 07:46 PM
I just put my 1C's into paint today
I am not sure what you mean. Are you painting it yourself? If so what king of paint are you using? I painted just the black base part on one of my speakers to see how well I could paint it. It came out Ok but i am hesitant to paint the top part.

mrappe
01-16-2012, 08:23 PM
In my haste to get my crossover back in I made the mistake to drilling too close to the smaller vertical coil and broke two or three of the wires in the coil. I don't know what the specs on it are or how to replace it. does anyone have an idea? In the mean time I am going to try to fix it.

Artifact
01-16-2012, 10:43 PM
what king of paint are you using? I painted just the black base part on one of my speakers to see how well I could paint it. It came out Ok but i am hesitant to paint the top part.

Hi mrappe, I painted my cabinets with Benjamin Moore Collection Black Alkyd Enamel Black F235 80 using a small roller and a quality 1" brush. It required two coats on the sides, the first coat looked like H**L but looks great now after the second coat. I'm planning to do a third coat on the top. The big issue with the top is of course painting around the Heil and the L-Pad controls. Easy enough to mask off the controls but the Heil is a problem to paint around. Next time I would remove the Heil so I can use a roller more effectively....however, this is just one more thing that I don't want to do at this point in time.

Artifact
01-16-2012, 10:51 PM
In my haste to get my crossover back in I made the mistake to drilling too close to the smaller vertical coil and broke two or three of the wires in the coil. I don't know what the specs on it are or how to replace it. does anyone have an idea? In the mean time I am going to try to fix it.
I have looked all over the net for an ESS AMT1b crossover schematic but to no avail. I even emailed ESS and requested one, however there was no response. Unfortunate, since ESS could really capitalize on showing potential new customers that they support past owners with historic speakers by putting historic technical info up on their website.

Artifact
01-16-2012, 11:04 PM
a small roller and a quality 1" brush.

Note, it was a foam roller, better for smooth application.

mrappe
01-16-2012, 11:44 PM
I have looked all over the net for an ESS AMT1b crossover schematic but to no avail. I even emailed ESS and requested one, however there was no response. Unfortunate, since ESS could really capitalize on showing potential new customers that they support past owners with historic speakers by putting historic technical info up on their website.

It would be nice if they would give some support. I repaired the break and rewound the coil using a wooden dowel the same size as the paper tube. If worst comes to worst. I can measure the length and wire diameter if I need to make another one or find someone that sells them.

Boto
01-17-2012, 07:59 AM
I have looked all over the net for an ESS AMT1b crossover schematic but to no avail. I even emailed ESS and requested one, however there was no response. Unfortunate, since ESS could really capitalize on showing potential new customers that they support past owners with historic speakers by putting historic technical info up on their website.

Might have got lost in the shuffle, considering the CES show was last week. I emailed them a request last fall for a crossover schematic for my old PS-8's. They were very happy to send it to me. They even pulled the original and read me some of the values that were hard to read on the PDF they sent me.

Artifact
01-17-2012, 12:04 PM
Well heck, I emailed them on November 18th. I think part of the problem is that they are understaffed. The ESS CEO handles almost all telephone calls and receives all email from their website contact page.

sti2k5
01-17-2012, 12:18 PM
I actually am having them sprayed by a professional auto shop we have at my dealership.
They were going to get a matte black but we realized with that finish you can't buff imperfections out, so now I'm going with a high gloss black and will just not put the grilles back on...Pics on my thread later

mrappe
01-17-2012, 03:28 PM
Might have got lost in the shuffle, considering the CES show was last week. I emailed them a request last fall for a crossover schematic for my old PS-8's. They were very happy to send it to me. They even pulled the original and read me some of the values that were hard to read on the PDF they sent me.

I just got off the phone with the CEO and he said that the 1B's is one that he does not have. He said that I talked to one of the designers of the original and was going to try to get him to help him draw one. I sent him a picture of my updated crossover and the original.

mrappe
01-17-2012, 03:32 PM
I actually am having them sprayed by a professional auto shop we have at my dealership.
They were going to get a matte black but we realized with that finish you can't buff imperfections out, so now I'm going with a high gloss black and will just not put the grilles back on...Pics on my thread later

I would like to see the results. I painted the bottom of one with Krylon Matte Black after a lot of sanding and primering with black primer then sanding the primer with 320 grit. It came out pretty good bit a lot of work. I have hesitated to do the top since I dont want to mess up the plate where the adjustment controls are.

sti2k5
01-17-2012, 05:05 PM
I would like to see the results. I painted the bottom of one with Krylon Matte Black after a lot of sanding and primering with black primer then sanding the primer with 320 grit. It came out pretty good bit a lot of work. I have hesitated to do the top since I dont want to mess up the plate where the adjustment controls are.

My 1 plate was trashed, but I saved it with some clear tape, and scraped it off...the other one was ok, but I took it off anyway...I will get new labels...but here is a picture of what it looks like currently...
Should have paint in the next 2 days...going for high gloss black :D

Artifact
01-18-2012, 01:56 AM
Ever worked on something audio for a couple of months and finally hooked it up with fear and trepidation that the right channel will be nothing but crackle or it will just sound like s__t but find that it is a revelation, a contracted ball of musical mush that has expanded into a new universe? I finally got the ESS AMT1b's up and running late this afternoon and some of the words that came to mind as I was listening tonight are: clarity, dynamic, smooth, coherent, effortless, articulate, integrated, glareless, detailed, stressless, clean, revealing, and musical. Not hyperbole, just amazing the difference. Can hardly wait until tomorrow! Yes, I had a few beers to celebrate. Thanks to all who provided advice.

sti2k5
01-18-2012, 01:28 PM
so do you think it worthwhile to send these to ESS? I've been reading some old threads that they didnt know what they were doing anymore..?

mrappe
01-18-2012, 05:16 PM
so do you think it worthwhile to send these to ESS? I've been reading some old threads that they didnt know what they were doing anymore..?
Sorry but I have to ask:To do what? if you mean refoaming etc. I would think that they should be abe to do it OK. I have to reviewed any of their newer speakers so I cannot personally comment on them. According to what I was told by the CEO was that everything was being made in and the materials were from the US so it would sound to me that they want to have a quality product.

Artifact
01-18-2012, 09:35 PM
I'm very interested in hearing how those new ESS paper woofers sound.

You asked me earlier in this thread to comment on the new ESS 12" coated paper woofer once I had it installed. I have done about 6 hours of listening so far. I tested for acoustic bass on several jazz records including Bill Evans at the Village Vanguard (Scott Lafaro on Bass) and for Rock Music, Audioslave and Pink Floyd among others. In comparison to the old bextrine woofer this one is more extended, more revealing of detail, up front without being exaggerated, and has the speed to sync up with the Heil. It is what I would call tight bass, definitely not one of the bloated, mushy or flabby types.

automojo
01-18-2012, 11:01 PM
Ever worked on something audio for a couple of months and finally hooked it up with fear and trepidation that the right channel will be nothing but crackle or it will just sound like s__t but find that it is a revelation, a contracted ball of musical mush that has expanded into a new universe? I finally got the ESS AMT1b's up and running late this afternoon and some of the words that came to mind as I was listening tonight are: clarity, dynamic, smooth, coherent, effortless, articulate, integrated, glareless, detailed, stressless, clean, revealing, and musical. Not hyperbole, just amazing the difference. Can hardly wait until tomorrow! Yes, I had a few beers to celebrate. Thanks to all who provided advice.

Awesome to hear!! I totally understand the trepidation-all that work and, I had they same feeling with my first pair of refurbed AMT3's. Managed to hook one of the woofers pretty much a dead short-the +/- from the crossover to the same two terminals on one side of the voice coil-luckily it did'nt damage anything-except for a little pride!
Great job, and well worth the effort!! Awesome.
Fill us in when the woofers have a chance to really break in-my 1040SF took around 10-15 hours to really loosen up. I'm a big fan of paper cone woofers, and think they match up well with the Heils, and don't loose their musicality like some plastic/composite can cones do. Although my PS1220's had Bextrene cones and sounded very good.
Thanks for the info and thoughts-much appreciated:thmbsp::music:
Please keep us posted!!

automojo
01-19-2012, 01:07 AM
As a side note, I finally took Ron's advice and ordered some Sonic Barrier for both sets of my AMTs.
I plan of lining the woofer cavity,and placing one sheet over the back/crossover as well.
I think the back sheet will make a larger difference then the 2 side sheets-but I'm hoping they will all work together well.
I have been doing alot of research on damping, and e-mailed of few fairly knowledgable people on the subject, and have come to the conclusion that using at least 2 different type of damping materials is advantageous as they seem to compliment each other in most instances of a varity or reaosn-that I will try to pass on on my AMT3 thread when I get the change, and see how this preforms in my 1st set of AMT3's.

mrappe
01-19-2012, 04:18 PM
Congratulations, I too hooked mine up last night after I repaired the coil that I broke. I was afraid that it would not sound good because of that but it sounded better that it did before. It was not a very dramatic change because it sounded good to begin with but it may now sound better then the other one that i have not done yet which had sounded better. My "put together" was just to test if the crossover was working as I still have to take it apart and do a few other things such as sealing the wire hole for the heil and adding gasket material to the speaker mount. I am glad to hear of your success!

Artifact
01-19-2012, 05:01 PM
I was afraid that it would not sound good because of that but it sounded better that it did before. It was not a very dramatic change because it sounded good to begin with but it may now sound better then the other one that i have not done yet

I've noticed that the sound of the Mundorf Caps has changed over the first couple of days - I listened to some Vanessa Paradis and Diana Krall early on. After listening again today I found their voices more rounded and warm - in a very good way. Also, after blathering on about how great my speakers sounded after 6 hours of listening, I realized today that I was being way too conservative with the new L-Pad presence and brilliance controls as I had set them at middle volume for installation. I decided to jack them both up considerably. Although I was concerned that this might make them sound brittle or glarey, it produced an overwhelmingly positive effect. Let's see, what can I fiddle with next...

mrappe
01-20-2012, 08:23 AM
In comparison to the old bextrine woofer this one is more extended, more revealing of detail, up front without being exaggerated, and has the speed to sync up with the Heil.

What does the bextrine woofer look like because the ones in my AMT1Bs look like paper to me but i don't know what bextrine cones look like

automojo
01-21-2012, 10:55 AM
What does the bextrine woofer look like because the ones in my AMT1Bs look like paper to me but i don't know what bextrine cones look like

Bextrine is a form of poly-essentially a plastic. Alot of manufactors were using types of poly woofers back then because the thought was they were superior to paper, wouldn't deteriorate etc.
However, some actually where less stiff then paper, many were heavier.
They usually used another material mixed with the poly/plastic to increase stiffness-but this also addd some weight.
My old ESS PS1220's had plastic woofers- and sounded good-but the paper are definitly 'quicker', and have more detail IMHO-and seem a overall better match to the Heils.
Probably why ESS went back to paper. Most paper cones are treated so they usually hold up ver well over time.
ESS also chose to implement rubber surrounds-which is good and bad-as there is a train of thought that foam surrounds better position the cone for truer 'piston' motion, were rubber is too compliant. And ruuber provides better damping-but you loose sensitivety. However any well designed driver can over come this, and usally applys only to the lowest cost drivers.

mrappe
01-21-2012, 01:05 PM
Does the Bextrine look shiny and smooth? Do you know of any pic of one?

mrappe
01-21-2012, 01:06 PM
On doing research on building a coil/inductor/choke I found this:
http://www.electronics-diy.com/product_details.php?pid=500&name=Special Edition Accurate LC Meter Kit with Green Backlight LCD - <font color=green>FREE CASE</font>
This might be a good way to measure the other coil. Does anyone know anything about this meter?

automojo
01-21-2012, 01:27 PM
Bextrine looks like a poly woofer-black and shiny-just google a ESS AMT 1, and you will probably find one.
http://www.ebay.com/itm/ESS-AMT-1C-SPEAKERS-Large-Heil-Air-Motion-Transformers-REFOAMED-PASSIVES-WOOFER-/300620333514
Parts Express also has a LC meter, I know some are more accurate then others-not sure on that one.

mrappe
01-26-2012, 05:34 PM
I put some Hurricane Nuts on the speaker that I re-capped but 2 of them keep comming out even though I glued them pretty well. I will have to try something else.

Artifact
01-26-2012, 06:53 PM
Maybe send Ron-c a private message and ask how he glued/installed his as I think it was Ron who recommended the hurricane nuts.
Cheers!

automojo
01-26-2012, 11:07 PM
You need to use epoxy to attach the Hurricane nuts in-slow dry is best- and let them set up for 24-48hr. Don't mess with them before the glue has set properly-as even 'quick dry epoxy need 24 hrs to truely set up. Slow dry is the best, as is is by far the strongest of the 2.
I put glue on the inside flange-then once pushed in, apply the glue to the outside flange as well that faces the interior.
If you install the scew and lube it up with silicone grease, the epoxy won't stick to it or get in the threads.
I have removed my woofers in my first set at least 10 times + without a single problem attaching them this way.
The ESS baffles aren't suited the best to regular t-nuts, as they are to large, and require a pretty good force to seat them.
Clean of all the old glue the best you can, and follow the above instructions- and I guarantee they will work fine.
I used the #8 ones by the way.
You also should epoxy the sealing edges to strengthen them
There are quite a few threads on dealing with refurbing ESS cabs-good reading and should be helpful to you.

mrappe
01-28-2012, 12:57 PM
Bextrine looks like a poly woofer-black and shiny-just google a ESS AMT 1, and you will probably find one.

These are my woofers. I think that they were reconed with paper when they were refoamed several years ago. otherwise ESS made some AMT1Bs with paper woofer cones.
http://i1202.photobucket.com/albums/bb376/mdrappe51/ESSWoofer_01282012_004826_0003.jpg
http://i1202.photobucket.com/albums/bb376/mdrappe51/ESSWoofer_01282012_004741_0001.jpg
http://i1202.photobucket.com/albums/bb376/mdrappe51/ESSWoofer_01282012_004846_0004.jpg

Artifact
01-29-2012, 07:35 PM
words that came to mind as I was listening are: clarity, dynamic, smooth, coherent, effortless, articulate, integrated, glareless, detailed, stressless, clean, revealing, and musical.

Just a few more comments on my AMT1b rebuild after2 weeks of listening.

System Volume Increase
Since rebuilding my 1b pyramids I have experienced a major increase in sound volume. Whereas in the past I played most CD's at about 9:30 on the volume dial I am now playing them at about 8:00 on the dial and 8:00 is fully detailed, loud, and full of punch and dynamics. I'm attributing this increase to the higher voltage caps and crossover/cabinet rewire (Audioquest 18awg). Some remasters are actually too loud at 8:00, and since volume and dynamics drop off too rapidly below 8:00 I am going to test using the variable outputs on my CD player.

New ESS Paper Cone Woofers
I previously reviewed these in the thread after 6 or 7 hours of listening. After two weeks listening and breaking in they are putting out at least another 25-35% of Bass, particularly at the low end. The bass on Joan Armatrading's "Willow" and other heavy bass selections is something that must be heard to be believed!

New Yung LP50 L-Pads
Very quiet and clean. I fiddled about with the volume levels for both brilliance and midrange controls for several hours with different kinds of music and finally settled on the lower end of what ESS calls the optimum range for each control. This provides lot's of presence and high frequency detail, great soundstage, and low fatigue listening on 90% of my CD's. One or two remasters seem totally overblown on these settings but I think in some cases they dial up the mids and highs to the extreme for the folks with impoverished mid and high frequency systems. I bought a Jimi Hendrix remaster a couple of days ago and found it detailed but also so dry and clinical that I'll probably never play it again…On the other hand Paul Simon's Graceland remaster is fantastic!

Passive Radiator Concerns Resolved
In an earlier post I had concerns about the polyester stuffing interfering with the PR if it came in contact with it. This potential problem was resolved by stuffing the top back of the cabinet with pieces of polyester fill that were long enough to extend beyond the inside edges of the cutouts. Also, I placed the wires from the crossover to the binding posts immediately behind the PR's (1" clearance approximately, including the 1/2" felt and cabinet walls) so they served as as retainer for the fill. It works, there is lots of vibration coming from the PRs.

Anyway, I can't believe that I have gone on listening to these speakers stock for 33 years. For anyone contemplating a rebuild, believe me, you will be amazed at the difference!

mrappe
01-29-2012, 08:25 PM
That is great to hear. Thank you for the update. Did you get the new PRs that have a basket?

Artifact
01-29-2012, 10:11 PM
I still have the old PR's. Maybe next year I'll spring for the new basket-style PR's - spent too much money already. I checked out your woofer pics, definitely not bextrene. I doubt that ESS reconed them - maybe Orange County Speakers or a local hifi shop with a good technician. Are you on the west coast? Curious about the history of your speakers...

automojo
01-29-2012, 11:56 PM
Just a few more comments on my AMT1b rebuild after2 weeks of listening.

System Volume Increase
Since rebuilding my 1b pyramids I have experienced a major increase in sound volume. Whereas in the past I played most CD's at about 9:30 on the volume dial I am now playing them at about 8:00 on the dial and 8:00 is fully detailed, loud, and full of punch and dynamics. I'm attributing this increase to the higher voltage caps and crossover/cabinet rewire (Audioquest 18awg). Some remasters are actually too loud at 8:00, and since volume and dynamics drop off too rapidly below 8:00 I am going to test using the variable outputs on my CD player.

New ESS Paper Cone Woofers
I previously reviewed these in the thread after 6 or 7 hours of listening. After two weeks listening and breaking in they are putting out at least another 25-35% of Bass, particularly at the low end. The bass on Joan Armatrading's "Willow" and other heavy bass selections is something that must be heard to be believed!

New Yung LP50 L-Pads
Very quiet and clean. I fiddled about with the volume levels for both brilliance and midrange controls for several hours with different kinds of music and finally settled on the lower end of what ESS calls the optimum range for each control. This provides lot's of presence and high frequency detail, great soundstage, and low fatigue listening on 90% of my CD's. One or two remasters seem totally overblown on these settings but I think in some cases they dial up the mids and highs to the extreme for the folks with impoverished mid and high frequency systems. I bought a Jimi Hendrix remaster a couple of days ago and found it detailed but also so dry and clinical that I'll probably never play it again…On the other hand Paul Simon's Graceland remaster is fantastic!

Passive Radiator Concerns Resolved
In an earlier post I had concerns about the polyester stuffing interfering with the PR if it came in contact with it. This potential problem was resolved by stuffing the top back of the cabinet with pieces of polyester fill that were long enough to extend beyond the inside edges of the cutouts. Also, I placed the wires from the crossover to the binding posts immediately behind the PR's (1" clearance approximately, including the 1/2" felt and cabinet walls) so they served as as retainer for the fill. It works, there is lots of vibration coming from the PRs.

Anyway, I can't believe that I have gone on listening to these speakers stock for 33 years. For anyone contemplating a rebuild, believe me, you will be amazed at the difference!

Nice job, and awesome descriptions of your thoughts!:music:
I'm sure your increased the efficinecy of your crossover, and this accounts for, as well as the new woofers, for the increase in output-all good things-IMHO speaker should be efficient-not slugs!:thmbsp:
Your thread will be a good inperation to other ESS onwers to get off theri duffs and get those awesome speakers back up to snuff (and perhaps prevent the dreaded cannabilization:sigh: of these awesome speakers!
Just goes to show, some elbow grease and few new upgraded and refreshed parts will get the Great Heil speaker to really sings.
Thanks again, all the info and descriptions is much appreated!
Welcome to the ESS Heil Rebuilt Club!

automojo
01-29-2012, 11:59 PM
These are my woofers. I think that they were reconed with paper when they were refoamed several years ago. otherwise ESS made some AMT1Bs with paper woofer cones.
http://i1202.photobucket.com/albums/bb376/mdrappe51/ESSWoofer_01282012_004826_0003.jpg
http://i1202.photobucket.com/albums/bb376/mdrappe51/ESSWoofer_01282012_004741_0001.jpg
http://i1202.photobucket.com/albums/bb376/mdrappe51/ESSWoofer_01282012_004846_0004.jpg

Those are stock, and look like stock cones. ESS used paper and Bextrine, finally settling on Bextrine on the later models. You should be fine with those till the need new surrounds. The newer surround will last far longer then the ESS stock ones-as the foam technolgy has improved since then.

mrappe
01-30-2012, 07:01 PM
I was assuming that they had been refoamed since I find it hard to beleive that 33 year old surrounds weould look this good. The AMT1s that I had were purchased in 1973 and by 1979 they were rotted.

Artifact
01-30-2012, 08:57 PM
I am curious as to what the rest of you ESS fans, freaks, et al, are using as source equipment, brand and model number and your opinion of them, since this is pretty crucial to the sound of the Heils in particular. Although I have a Rega Planar 3 I regret that I gave up most of my record collection years ago so I seldom use it. I'm currently using my Denon DCD 2560 pretty much exclusively and although I'm still very happy with it, it's old and I'm thinking of going with either an add-on DAC or completely new CD Player. Since I suspect that many electronic components in the Denon need replacing, my choice will probably be a new CD player. Although I haven't done too much research yet, the Marantz CD6400 seems to be regarded highly in the $500 range, although I'm prepared to spend somewhat more. Definitely, I would like to listen to any potential equipment in my own system before purchasing, but this seems less likely these days. I would ultimately like a CD player that has warm yet detailed mid and high frequencies, good sound stage, and is also capable of kicking out a lot of good bass.
The few negative comments about the Denon 2560 have described it as digital sounding and lacking in bass. Don't really agree with these comments and feel they are based on some other equipment issue in their systems. That being said, I haven't really tried any other CD players in my system...
Anyway, over to you…. also feel free to mention any other equipment that you believe has made a major difference in your ESS system.

automojo
01-31-2012, 12:24 AM
I have pretty much settled on Harman Kardon amplification over the years-and they seem to work well with a variety of speakers. I currenty use a PT2300/PA2400 combination to drive my first set. (170 wpc) And my second set will be driven by a Citation 21/Signature 1.5 (350 wpc@4 ohms). Both combinations are fairly neutral (hate to use that word)-but have plenty of drive in the bass department, and excellent woofer control.
The Signature will drive anything you throw at it, as well a the PA2400-it just runs out of steam before the 1.5.
As with my experience with Klipsh-even thoe ESS speaker are fairly efficient- throwing some nice clean power at them really makes them different animals-even at low-to medium listening levels.
I love my Teac PD-H600. It has a huge sounstage but plenty of bass drive
CD players need a good power supply to give your sound real weight-and this player has that, and is a excellent match to my AMT3's-in fact this was the reason I got it, because my Marantz wasn't really cutting it. I tried a few different models- and settled on this was as sounding the best for under $1K.

Artifact
01-31-2012, 10:25 PM
Thanks for the info on your amplification and source equipment. I read some reviews for your HK amps and the Teac CD player. They all get great reviews and must sound incredible with your AMT3's. Although I used to own a Teac tape deck I haven't seen any Teac equipment in Victoria for a number of years. Many of our smaller specialty Hi-Fi stores have gone under with the advent of the big chain stores. Will definitely take a listen if I can find any dealers nearby!

mrappe
02-01-2012, 12:07 AM
I just got my re-capped speaker back together with the hurricane nuts firmly in place and new speaker gasket on both. I also just got my Marantz 2275 back from being fixed and re-capped so now I can make a better comparison of both the re-capped and original capped speakers because the Marantz has the ability to switch for Mono. My HT reciever does not have that so It is hard to compare both channels.I left the wiring from the speaker jacks to the crossover and the wired to the woofer and tweeter as the thin original wiring. I was afraid that going to larger wiring thru out the speaker would lower the resistance from the original specs to much

automojo
02-01-2012, 11:23 PM
Thanks for the info on your amplification and source equipment. I read some reviews for your HK amps and the Teac CD player. They all get great reviews and must sound incredible with your AMT3's. Although I used to own a Teac tape deck I haven't seen any Teac equipment in Victoria for a number of years. Many of our smaller specialty Hi-Fi stores have gone under with the advent of the big chain stores. Will definitely take a listen if I can find any dealers nearby!

I was a little skeptical on the Teac at first-because the hadn't seemed to made any really decent equipment since the glory tape deck days-but once I learned they built Esoteric gear, and looked at some of the pro reviews-I thought it was worth a listen-plus most retailers offer a 30 day try out with no cost.
Not cheap-but well worth the cost in my opinion over the long haul if you still listen to cd's alot-which I do. If the build of this deck translates into the longevity-it should last for quite a few years.
The NAD decks I audiioned had too much coloration for me, and a "fake spaciousness" sound that was very apparent with the Heils-like they tried to hard to sound hifi-the Teac just let's the sound flow.
Plus the realibilty of NAD cd playes leaves alot to be desired. Too bad-if they just spent a few more dollars, and charged a few more they could avoid the problem.
The NAds' probably would sound good on a dark sounding set of speakers-but not the best with Heils IMHO.
Nice thing about H?K amps- at least the PA2400,usually you can get them for under $300, same with the preamps. THe PT2300 really is a stellar performer, and the remote is a bonus.

Artifact
02-02-2012, 12:25 PM
I left the wiring from the speaker jacks to the crossover and the wired to the woofer and tweeter as the thin original wiring. I was afraid that going to larger wiring thru out the speaker would lower the resistance from the original specs to much

I think you were wise to be cautious concerning the wiring. The 16 gauge wire I used is really too big for these speakers/crossovers. As noted in one of my previous posts my rewire with 16 gauge has resulted in a substantial increase in volume: I am now playing most of my CD's at the first volume detente on my preamp, 8:00 o'clock. The sound level, although still comfortable, is as loud as you would reasonably want. Some CD's that have been recorded at higher recording levels are difficult to control since dynamics and sound levels drop off quite dramatically below 8:00 o'clock. As previously noted I was going to test using the variable outputs on my CD player to see if the additional volume control would help. Unfortunately, I have discovered that the volume pot for the variable output is either dirty or fried. Will have to fix and retest.
By the way, I actually never rewired with 16 gauge from the crossover to the Heils. Although I really will consider every other option first, if I decide on some rewiring, I would probably start with restoring the original wire size, or slightly larger, from the binding posts to the crossover and test. Should provide a bit more impedance. Not really in the state of mind to consider any crossover re-wiring yet. The system sounds great, just don't have enough control over volume.
Anyway, mrappe, am looking forward to your listening tests!

mrappe
02-02-2012, 07:48 PM
The system sounds great, just don't have enough control over volume.


Why is that? I am not sure that I understand. I just got my Marantz 2275 back from re-capping So I am also testing on that instead of my HT receivers.

Artifact
02-03-2012, 10:16 PM
I think you were wise to be cautious concerning the wiring. The 16 gauge wire I used is really too big for these speakers/crossovers. As noted in one of my previous posts my rewire with 16 gauge has resulted in a substantial increase in volume

After speaking with the best audio technician in Victoria (Aaron at Sound Hounds), I feel I should retract the above statement. Aaron, who has successfully rebuilt dozens of speakers, suggested that my volume issue (if it exists) is probably more to do with the added dynamics and clarity of the new caps and the contribution of the many other changes I have made to the speakers rather than just wire size. In brief, the lengths and size of wire involved in my re-wire compared to the originals would not account for a substantial volume change. He also advised that given the relatively small amount of listening I have done, the speakers and new components need quite a bit more time to break in properly. So… no more fatalistic comments about sound or volume until I have put significantly more hours on the rebuild. I am currently using the Repeat All (continuous replay) function on my CD player to shorten the break-in period while I'm not listening.

mrappe
02-04-2012, 03:06 AM
I may be wrong about this but until reciently getting on AK I have never heard of "breaking-in" either speakers or electronic audio equipment. The concept seems strange to me. Is is a mechanical or electronic phenomena?

Artifact
03-01-2012, 03:09 PM
I just got my re-capped speaker back together
Hi MRAPPE, Are your speakers up and running and if so how do they sound?
Regards!

mrappe
03-02-2012, 04:02 PM
I have still only redone the left speaker. On purpose, so that I can compare the differences if any. I noticed a slight improvement in the updated speaker but it is very slight. I think that that was because the speakers had been refoamed before I bought them about 7 years ago and were in good contition to begin with. Even though the xover had not been redone on the left speaker and the right speaker has had one bad cap replaced several years ago before I bought them. They have always sounded great. I think that what I am getting out of the re-capping is the sense of assurance that they won't go bad in my lifetime. How are yours doing?

mrappe
03-11-2012, 08:22 PM
Strange things are afoot at the Circle-K. Last night I took the Xover out of the AMT1B that I have not re-capped yet and measured (with my new LC meter) the equivalent inductor coil (after unsoldering it) that was damaged on the speaker that was re-capped. I then measured the one one on the recapped speaker that was re-capped and found that the valve was way off (no big surprise there). I then put both speakers back together and listened to them to make sure that I got all of the wires on. I found that the re-capped speaker sounded much more open and detailed than the other. Lately I have not be listening to these speakers but some that I just bought off of CL. My son has been listening to them though. The un recapped speaker sounded slightly duller and I am not sure if I had just dome something to it last night when i was measuring the coil or if it was a case of the re-capped one now just sounding much better. The strange thing is that the re-capped one has the bad inductor coil in it.

Artifact
03-11-2012, 08:48 PM
The un recapped speaker sounded slightly duller and I am not sure if I had just dome something to it last night when i was measuring the coil or if it was a case of the re-capped one now just sounding much better. The strange thing is that the re-capped one has the bad inductor coil in it.

Wow, interesting! If the one with the bad inductor sounds much better, it will be exciting to find out how the other speaker with the good inductor sounds when recapped.

Artifact
03-11-2012, 09:25 PM
How are yours doing?

I'm really enjoying listening to mine although I'm coming to the conclusion that, as other people have suggested, what these speakers may need is a third purely midrange driver to perfect the AMT1b's sound. There are certain midrange frequencies that my 1b's do not appear to reproduce well, particularly noticeable with some voices. I recently updated almost all of my iTunes songs added from my CD's to Apple Lossless Format (original CD quality format) and purchased a reasonably high quality set of earbuds (Klipsch S4's) for my Ipod Classic. I must say that this has resulted in some super listening experiences - loads of bass and high frequency detail, as well as a very smooth sweet midrange. For the $80 bucks spent on the earbuds, I am impressed!
All the above having been said I can't necessarily shoot down the 1b's based on the comparison. Source is everything and my Denon 2560 CD player is almost 20 years old and could be to blame for some midrange frequencies sounding somewhat hard. Other possible issues could include bad mylar diapraghms on the AMT's(33 years old), or the fact that I did not replace the original wiring to the AMT's when I rewired. In fact the number of equipment issues that could bear on the signal reaching my AMT's is pretty much endless. I guess my next step will be to thoroughly inspect the AMT diaphragms and think about getting a separate DAC or new CD player. Could also do a little more fiddling with the midrange and high frequency controls. Too bad we don't all have bottomless pockets!

Artifact
03-11-2012, 09:31 PM
Lately I have not be listening to these speakers but some that I just bought off of CL.
Curious, what speakers did you buy and how do they compare with the AMT1b's?

mrappe
03-11-2012, 11:00 PM
I got two pairs of speakers. They are good but not as good as the AMTs. i just like to listen to different speakers. You can see the thread at
http://www.audiokarma.org/forums/showthread.php?t=427766
and
http://audiokarma.org/forums/showthread.php?t=429884

el seven
03-17-2012, 06:46 PM
I scanned this thread and didn't read every post. Brief responses below:

I just got off the phone with the CEO and he said that the 1B's is one that he does not have. He said that I talked to one of the designers of the original and was going to try to get him to help him draw one. I sent him a picture of my updated crossover and the original.

I can give you any 1b component values you need, from my bible.

Sorry but I have to ask:To do what? if you mean refoaming etc. I would think that they should be abe to do it OK. I have to reviewed any of their newer speakers so I cannot personally comment on them. According to what I was told by the CEO was that everything was being made in and the materials were from the US so it would sound to me that they want to have a quality product.

There is a younger gentleman named Louis at ess that has over 15yrs of experience doing refoams, he's good to go on anything. Unfortunately it's not the case that the materials for recones and the new woofers are mfg'd in the US - Louis does the installs on the recones so at least there's something there. The woofers are produced in China and the cone / coil / spider /surround combo is from the same factory. Rico should be ashamed to be telling people that, as i figured he might. :( Louis is the only assy person there and he's a good kid.

Bextrine is a form of poly essentially a plastic. Alot of manufactors were using types of poly woofers back then because the thought was they were superior to paper, wouldn't deteriorate etc.

Probably why ESS went back to paper. Most paper cones are treated so they usually hold up over well over time.

ESS also chose to implement rubber surrounds which is good and bad as there is a train of thought that foam surrounds better position the cone for truer 'piston' motion, where rubber is too compliant. And rubber provides better damping but you lose sensitivety. However any well designed driver can over come this, and usually applys only to the lowest cost drivers.

They went with poly-mica sprayed paper for purely economic reasons. Same could be said with the n-butyl surrounds. Combined they accounted for the lowest cost driver and as you suggest, the response characteristic is on the lower end of dbspl woofers. Those bextrene coned units with poly-ether suspension put forth considerably better sensitivities than the sprayed paper and rubberized do. Lack of sensitivity however, can be overcome EVEN with the budget driver! It would take a 4-layer ribbon VC, an anodized bobbin, and a vented motor structure to accomplish this generally speaking due to increased power consumption where heat will be a death nail.

Does the Bextrine look shiny and smooth? Do you know of any pic of one?

Bextrene cone material isn't shiny. Think "dull satin" sheen and a non impregnated smooth texture. Polypropylene gets it shiny surface from poly-mica injection during the mfg process. Bextrene material has no poly injection.

These are my woofers. I think that they were reconed with paper when they were refoamed several years ago. otherwise ESS made some AMT1Bs with paper woofer cones.

http://i13.photobucket.com/albums/a293/83fj/mrappe1b.jpg


Not stock... the whole driver was re-coned stem to stern. :) The 1b never utilized a paper driver, you'd have to go back to the 1a to see pulp cones. Looks to me like decent diaphragm material and surround for the job but the paper cap defeats some of the efficiency of that motor structure.

All in all it's ESS day again! :D

L7

mrappe
03-18-2012, 03:55 AM
I can give you any 1b component values you need, from my bible.

The coil value (the coil that I messed up) that I finely was able to measure with my LC meter was showing as 0.158 mH on the other crossover and I need to know if this is correct so that I can replace the damaged one.

el seven
03-18-2012, 02:53 PM
The coil value (the coil that I messed up) that I finely was able to measure with my LC meter was showing as 0.158 mH on the other crossover and I need to know if this is correct so that I can replace the damaged one.

I posted in a thread about this very recently, i thought it was this thread but must have been another. Yes the value is precisely .160mh on that inductor and .160 is a readily available value.

JimPA
03-18-2012, 09:04 PM
In response to the bextrene questions.

Spendor still use bextrene in the 30cm cone of the model SP100R2.
All bextene cones are damped with plastiflex.

Focal Neoflex cones is their form of bextrene . They claimed it ti be stiffer then polypropylene. It is also coated with plastiflex.

Most were low sensitivity. Then there were other versions like Automojo stated.

Some were thinner and high sensitivity which were oem versions with large magnet structures.

Most of the people involved with their designs are no longer with us.

One reason bextrene was phased out was how it could not withstand the heat for autosound.

It would take a chemical engineer to explain the differences between all companies versions with it being isotropic bextrene.

I have some higher sensitivity 6.5" versions in my avatar.


http://www.audiokarma.org/forums/showthread.php?t=124795

mrappe
03-19-2012, 01:29 PM
I have ordered the caps for my second speaker now that I can audibly hear the improvement in the first (recapped) speaker. It is interesting that the recapped speaker sounds better even though one of the inductors is not functioning correctly. I measured the good inductor coil on the other speaker and it is about .158 mH and the resistance is between 3-4 Ohms but I don't know the gage of the wire. How do you measure the gage of the wire?

flyby
03-25-2012, 01:27 AM
can someone please explain why the lpads are 8 ohm when the rest of the board is 4 ohm. i need new pads also. thanx

Artifact
03-26-2012, 09:58 AM
I assume that the 8 ohm lpads provide a variable resistance to the current running to the Heil of 0 to 8 ohms - to increase or decrease volume of mid frequency and high frequency sound.

jim1274
07-24-2013, 09:09 PM
I am in the process of rebuilding my AMT1b's and developed a checklist compiled from this and other AMT rebuild threads, so thought might be worth posting for a starting point for others undertaking the same project in the future. This would have been useful to me for a starting point, so maybe will be helpful to others.

This is generic and does not include part numbers and sources, plus I am making a few custom mods to mine beyond this list, but can add more specifics if anyone has interest.

If any of you rebuild pros see something I missed, add it on!

CABINET

Interior
Reinforce joints with wood glue as needed
Seal joints with silicon sealer
Inspect lower and upper chamber stuffing; reposition or replace (in kind) as needed; optional selective addition of wall damping material (1/2" Sonic Barrier or similar to exposed upper cabinet surfaces)
Seal wire raceway from cabinet to tweeter and to binding posts

Exterior
Repair/Refinish walnut veneer as needed
Repaint base with flat black
Repair/repaint upper cabinet section with black semi-gloss paint

CROSSOVER
Replace capacitors with Dayton Polys
Replace resistor with Mills
Inspect all wiring and connections plus crossover components
Replace spring clip connectors with 5 way binding posts
Clean L-Pad controls with Faderlube--replace if noisy after clean/lube

DRIVERS

Passive
Rebuild with kit (add 4 quarters to middle of inside to approximate OEM wood block)
Add speaker gasket at reinstallation

Woofer
Replace surrounds
Add speaker gasket at reinstallation

Tweeter
Inspect diaphragms (examine closely with strong backlight) and replace if any wear or damage
Clean housing and repaint as needed

Grills
Clean and recover as needed

EDIT

Well, this apparently has been covered before--found another thread post with checklist for evaluation--thought it might be useful to include here for completeness in case others do not come across it:

http://www.audiokarma.org/forums/showthread.php?t=319491

CHECK LIST FOR OLD NEWLY AQUIRED AMT

VISUAL INSPECTION
BASS DRIVERS:
SURROUNDS BETWEEN THE CONE AND THE CAGE cracks and tears.
CONE: cracks and tears.
VOICE COIL: discolored signs of over heating.
PASSIVE RADIATOR: Check the foam surround for cracks and tears.
AMT DIAPHRAGM: Shine a bright light from the back and inspect the pleats from the front. s/b even pleats’ and show no signs of overheating and warping.

VOICE COIL for drivers: Press gently and evenly on the center of the cone to make sure it moves freely in and out with out any binding. If there is no movement the voice coil is probably fused from overheating.

DCR TEST: AMT s/b approx. 3.9-5.6 ohms but compare each of the pair to see if the readings are consistent.
direct current resistance
Defective if open or shorted

BASS DRIVER neighborhood of 3 ohms- varies with size and year of production.
PLEASE NOTE THESE ARE THE BEST FIGURES I HAVE AT THIS TIME FOR DCR will up date as more data is available.
Defective if open or shorted

Check crossovers for signs of failed components especially for components that show signs of discoloration and burning from overheating.

Capacitors: Look for signs of leakage or excessive heat
Check DCR for open or short.

Resistors:
Check DCR for open or short and compare against rated value.
Check for signs of overheating.

Inductors (coils):
Check DCR for open and shorts.
Check for signs of overheating.

Wiring and printed circuit board
Check for open circuit.
Check for excessive resistance.
Check all solder points for failed/poor connection.

jim1274
08-03-2013, 01:14 PM
As a side note, I finally took Ron's advice and ordered some Sonic Barrier for both sets of my AMTs.
I plan of lining the woofer cavity,and placing one sheet over the back/crossover as well.
I think the back sheet will make a larger difference then the 2 side sheets-but I'm hoping they will all work together well.
I have been doing alot of research on damping, and e-mailed of few fairly knowledgable people on the subject, and have come to the conclusion that using at least 2 different type of damping materials is advantageous as they seem to compliment each other in most instances of a varity or reaosn-that I will try to pass on on my AMT3 thread when I get the change, and see how this preforms in my 1st set of AMT3's.

I am at the final stage of complete rebuild of my AMT1b pyramids and the last thing to do before reinstalling all the parts is make a decision on adding any cabinet wall lining. I read all the earlier posts on damping and still am confused on the best course of action. Mine had been opened up before by prior owner to redo surrounds, so I can only assume the stuffing was not changed from factory spec. Mine had loose polyfill style pretty much completely filling the lower chamber, which I think can be refluffed and resused--have some acousti-stuff from PE on hand if needed. The top chamber has the original lambs wool looking stuffing on the sides--pretty good shape and intact so looks good to go.

There have been various suggestions on adding wall damping material of various types and in various places--can anyone add to the conversation what they specifically ended up doing and the impact on the performance? I was looking at the options of adding damping to the bottom section which has the ployfill and lining some or all of the exposed interior in the top section housing the drivers. I am thinking doing all of the above will overdamp the cabinet, but not sure what the sweet spot is for added damping, if any is even warranted--maybe ESS had it exactly right?

Here is what I have on hand for potential use:

Sonic Barrier 3/4"
Sonic Barrier 1/2"
AlphaDamp (http://alphadamp.com/index.php/)

I am wondering if the Alphadamp would have any benefit by adding mass and weight to all the walls? Maybe just line the bottom chamber? It should not have much impact on the action of the interior sound waves if I get it correctly. This stuff is used to treat and deaden sheet metal in cars for dampening. Anybody ever used something like this in their pyramids?

It seems the consensus is to use Sonic Barrier in the top section, but I am still confused on what specifically to line--add sonic barrier to all the surfaces not covered by the wool and the top which is pretty much covered with the crossover?

Artifact
08-03-2013, 11:31 PM
Hi Jim, I agree with almost everything you've said in your checklist except your recommendation for capacitors. Although some recommend the Daytons, I recommend doing your own research and buying the best capacitors you can afford and wait a few hundred hours before judging the sound quality. I also recommend rewiring from the circuit board to the binding posts with superior heavier gauge speaker wire. I didn't rewire from the circuit board to the amt as I was paranoid about making them brighter - although in retrospect I should have at least tried it. I am pleased with the felt that I used for damping - don't think it overdamped the cabinets and it certainly contributed to the improvement in sound quality. I am still very happy with the sound from the refurb work I did. Interestingly, I just had all the knob and tube wiring replaced in my house. The electrician found that the wall plug I had been using for my stereo had the polarity reversed (Hard to tell with knob and tube). When fixed this made a pleasant and fairly substantial change in sound quality - fuller, more detail, and also seemed to be punchier. Anyway, I firmly believe there are many equally excellent ways to execute a refurb. What did Mao say?: something like "Let a thousand voices contend"

jim1274
08-04-2013, 04:34 PM
Plenty of options for sure on caps--I went with Daytons based on generally considered to be solid quality. Have to be better than 33 year old NPE's. They also were physically smaller than most other polys which allowed me to fit them on the footprint of the xover board. It was tight, but worked. I opted not to rewire. I used a Mills low inductance wirewound resistor. Coils left stock. The pads were sticky but a dose of Faderlube took care of that.

Just wrapped the rebuild up a few minutes ago and only had time for a short audition in less than ideal conditions (basement shop rig with old MP3 player and old receiver) but was VERY IMPRESSED with what I heard These AMT's are some something special. I am very anxious to test them in a good room with a quality front end. The high end detail resolution and spacious soundstage was very seductive even in a crappy test system.

The only thing I think may need some fine tuning is the damping material. I covered most of the exposed top chamber with 1/2" sonic barrier and put a piece of 3/4" on the bottom of the lower section. That may be too much.

Did a few custom things on the outside--I will post some photos later. Since I opted to run without grill covers, I finished them with Duratex rolled to a medium pebble finish and added metal grills front and rear. I may add a metal grill cage on top of the tweeters too for a more finished look.

I am definitely an AMT fan now.

Artifact
08-08-2013, 12:53 PM
Would be interested in knowing what you are using for front end components and how the amt1b's sound with them. My front end components are a bit over the hill...

jim1274
08-09-2013, 09:27 AM
Would be interested in knowing what you are using for front end components and how the amt1b's sound with them. My front end components are a bit over the hill...

I doubt your front end is a weak link--I actually have the same superphon preamp (and superphon power amp) that was going to get a test run with the 1B's. My initial test was going to be putting them on my Denon AVR 4311 in the front position and trying some high bit rate stereo source files using the DAC in my TOTL Oppo for conversion.

Artifact
08-09-2013, 11:19 PM
I doubt your front end is a weak link--I actually have the same superphon preamp (and superphon power amp) that was going to get a test run with the 1B's. My initial test was going to be putting them on my Denon AVR 4311 in the front position and trying some high bit rate stereo source files using the DAC in my TOTL Oppo for conversion.

I'm impressed. The AVR 4311 looks like an excellent piece of equipment from the reviews I have read. My Denon DCD-2560 is from the early 90's and I'm thinking about pairing it with either a Music Hall 25.3 or Cambridge DacMagic DAC for, hopefully, a big improvement. A little worried about the age of the Denon as the laser is likely to go in the near future requiring a $200 outlay. Maybe just a new CD Player, I've been hearing good things about the Marantz 6004 at $500....or....or
Anyway let me know how your listening goes. The initial listening of new equipment always throws me into a psychotic state for about 50 hours until I have reassured myself that everything is fine if not fabulous and that it will get even better after the first 300 hours...

jim1274
08-14-2013, 11:43 AM
I'm impressed. The AVR 4311 looks like an excellent piece of equipment from the reviews I have read. My Denon DCD-2560 is from the early 90's and I'm thinking about pairing it with either a Music Hall 25.3 or Cambridge DacMagic DAC for, hopefully, a big improvement. A little worried about the age of the Denon as the laser is likely to go in the near future requiring a $200 outlay. Maybe just a new CD Player, I've been hearing good things about the Marantz 6004 at $500....or....or
Anyway let me know how your listening goes. The initial listening of new equipment always throws me into a psychotic state for about 50 hours until I have reassured myself that everything is fine if not fabulous and that it will get even better after the first 300 hours...

I ended up just throwing the 1B's into the side surround position in my main 7.1 rig--detailed test as primary front stereo speakers yet to be done. That said, they were VERY nice as surrounds--the bi polar and wide dispersion worked nicely.

Artifact
04-08-2014, 11:26 PM
Wow, I added a SimAudio 100D DAC to my system (as noted in my signature). CD player to DAC, DAC to Preamp. Major, major improvement in sound quality. Well, the CD player is 22 years old and DAC's have come a long way. This one uses a BurrBrown PCM1793 DAC. Amazing! The AMT1b's just keep sounding better and better....
John

decooney
04-09-2014, 12:28 AM
So true. It's great to see how folks are rediscovering the ESS AMT Heils. After 30 years, I'm doing the same with simple front end gear. Next I'll be trying a new tube amp on my DEC-AMT28 custom Heil based speakers. It's like rediscovering the speakers and the Heil AMTs all over again.

Artifact
04-10-2014, 05:35 PM
So true. It's great to see how folks are rediscovering the ESS AMT Heils. After 30 years, I'm doing the same with simple front end gear. Next I'll be trying a new tube amp on my DEC-AMT28 custom Heil based speakers. It's like rediscovering the speakers and the Heil AMTs all over again.

I'm really interested in finding out more about the DEC-AMT28 custom Heils and would like to follow your tube amp add-on experience. Is this covered, or going to be covered, in other threads. Anyway I would like to keep abreast of it all as I have looked seriously at tube amplifiers for my ESS Amt1b set up. Curious about finding a tube amp with enough power at the right price as well?
Thanks,
John

IBJamon
04-11-2014, 08:50 PM
I have several ESS speakers and I have thought about tube amps, but I don't want to give up that SS power... I heard a tube preamp hooked up through my SS amp and was impressed (it wasn't mine, so I had to give it back). That could be another way to go for good results. Just my $0.02.

IBJamon

Artifact
04-15-2014, 11:30 AM
I have several ESS speakers and I have thought about tube amps, but I don't want to give up that SS power... I heard a tube preamp hooked up through my SS amp and was impressed (it wasn't mine, so I had to give it back). That could be another way to go for good results. Just my $0.02.

IBJamon

Thanks , I'll definitely follow-up on the tube preamp advice :yes:

decooney
04-15-2014, 09:20 PM
I'm really interested in finding out more about the DEC-AMT28 custom Heils and would like to follow your tube amp add-on experience. Is this covered, or going to be covered, in other threads. Anyway I would like to keep abreast of it all as I have looked seriously at tube amplifiers for my ESS Amt1b set up. Curious about finding a tube amp with enough power at the right price as well?
Thanks,
John


Hello John,
Yes, I posted the DEC-AMT28 project here on AK. It was a long awaited project that I finally got around to doing this past year. I had a pair of AMT Monitors and 1Cs once using a few different high power solid state amps when I played music at much higher volume levels, more than a few decades ago. I was a former employee at ESS Labs and did product assembly for a year before going into college. It was always a dream to build my own AMT version and drive it with modern-vintage gear. Now days, playing tube through my recent DEC-AMT28 build has been a new and completely different experience - all new, all over again. It's hard to recommend a particular tube amp in your case. I'd say if you can find one and borrow one from a local dealer, or try looking for a used one to get an idea before jumping int full tilt, it's always an option. Some of the higher power amps don't sound as lush, IMO. I would not believed it myself unti I tried it on my own speakers, a really good 10w tube amp can be deceiving, sounding like solid state amps at 5x the power or more. You might check for good used deal locally and see if you can try before buy to make sure it matches your speakers okay first. if you want a great value, one of the tube amps I was considering before I bought my Cary Audio tube amp was one of the newer D.I.Y ST-120 tube amps that look like the old Dynaco ST-70. You can build it or find one used, or buy it assembled. PM me if you need more info. I'll share what i can if it helps.

decooney
04-16-2014, 12:53 AM
I have several ESS speakers and I have thought about tube amps, but I don't want to give up that SS power... I heard a tube preamp hooked up through my SS amp and was impressed (it wasn't mine, so I had to give it back). That could be another way to go for good results. Just my $0.02.

IBJamon


Agree. This is a really good way to go too and I thought it about it long and hard before I jumped into tube gear. I'd say if you want to crank it up quite a bit, using the tube pre and solid state amp in combination can give you a bit of the best of both worlds without sacrificing speed and impact.

As I'm learning first hand now as my tube amplifier is breaking in now, the Heils can sound magical all over again with nice tube gear. There is a lot of experimentation, trial and error, and product matching that needs to occur to find the right outcome. I came very close to doing this with a tube preamp only and still think its a really good option if you can find the right synergy between components.

Cactus Bob
04-16-2014, 10:34 AM
I pulled out my AMT 3 Rock Monitors last weekend and plan on using setting them up in my main rig this weekend. I bought a Mac C220 tube preamp a couple months ago and it has been revelation for my JBL 250ti's. It's probably the best upgrade I ever made. I'll be driving the AMT 3's with a Yamaha PC2002 (240 wpc) power amp. I'm looking forward to hearing the Heils with this set-up.

IBJamon
04-16-2014, 11:45 AM
That sounds great! I have a pair of AMT 3 mains myself, so I really look forward to hearing about your results!

IBJamon

Cactus Bob
04-16-2014, 11:58 AM
That sounds great! I have a pair of AMT 3 mains myself, so I really look forward to hearing about your results!

IBJamon

Thanks, Really looking forward to an extended listening session with this set up. I'll report my findings.

Greeter
04-16-2014, 01:17 PM
I pulled out my AMT 3 Rock Monitors last weekend and plan on using setting them up in my main rig this weekend. I bought a Mac C220 tube preamp a couple months ago and it has been revelation for my JBL 250ti's. It's probably the best upgrade I ever made. I'll be driving the AMT 3's with a Yamaha PC2002 (240 wpc) power amp. I'm looking forward to hearing the Heils with this set-up.

I also own a pair of AMT3s. Would love to hear your thoughts, comments on these.

Artifact
04-17-2014, 06:20 PM
Hello John,
Yes, I posted the DEC-AMT28 project here on AK. It was a long awaited project that I finally got around to doing this past year.

Hi, and thanks for all of the info about tube equipment. I'm going to start testing tube preamps and amps. I'm lucky in that I have a couple stores here that will let you take equipment for the weekend to audition. Was amazed by the walnut cabinets and quality of the crossovers in your DEC-AMT28 project!