ESS Heil Tweeter Diaphragms... when to replace?

Discussion in 'Speakers' started by brianjrealto, Sep 8, 2018.

  1. brianjrealto

    brianjrealto Well-Known Member

    Messages:
    539
    Location:
    Dallas, TX
    Hi all,

    I have a pair of the 2-way ESS Monitors with 12" woofer and a 12" passive radiator. found a picture from another thread of the same model I have, for reference below..

    The speakers were Mint condition ( all original) when I purchased them from the original owner a few years ago, just beautiful and all most made me shed a tear of appreciation for the opportunity to buy such Minty speakers I had been looking for for several years.

    Recently, I had the crossovers rebuilt with new caps and resistors, improved the sound to become "tighter", still sounded good as before the recap/rebuild.

    Questions-
    at what point do you consider it time for replacing the Heil Diaphragms?
    Do the Diaphragms degrade over time, or Oxidize in any way?
    Any measurements test of the diaphragms to do to confirm this?
    Any way to clean the Diaphragms once removed?

    for those of you that replaced the diaphragms, was there a noticeable sound improvement swapping the Old to new diaphragms?
     

    Attached Files:

     

    Please register to disable this ad.

  2. swechsler

    swechsler Frog Whisperer

    Messages:
    4,886
    Location:
    7th row center
    Nice speakers. In my experience the diaphragms don't wear out, so unless they stop working or start sounding distorted, IMO you're just wasting money if you replace them.
     
  3. BilboBaggins

    BilboBaggins AK Subscriber Subscriber

    Messages:
    3,309
    Location:
    Ottawa, Canada
    I replaced one on an AMT1 pedestal. It was a victim of clipping. I didn’t notice a difference from when the old one was working.
     
  4. puppet

    puppet Active Member

    Messages:
    120
    The newer diaphragms have a mesh cover over the pleated section. The originals do not. The mesh keeps the pleated section aligned. Mine have been replaced over the years as the original began to deform and eventually tore along the fold line in a couple places. The newer diaphragms sound just fine.
    Nothing to clean, old or new.
     
  5. brianjrealto

    brianjrealto Well-Known Member

    Messages:
    539
    Location:
    Dallas, TX
    thanks for all the feedback! much appreciated..

    I'm ordering a new pair of diaphragms. I'll try the new diaphragms and report back what I found with the old ones once they are removed and I can get a close up look over them.
     
  6. jcidave

    jcidave Member

    Messages:
    52
    Location:
    Williamsburg, VA
    I agree that there should really be nothing to do from a maintenance standpoint for diaphragms. they work or not and there is really no need to change them if working. Only the oldest versions had no bridal veil. By the mid to late 70's the veil was already being being added. Your Monitors would have had them as OEM. My AMT3's did not have the veil, still have original diaphragms and sound fine. Diaphragms went through many iterations over the decades from number of pleats to type of substrate. At one point, ESS used Dupont Kapton as the substrate. They were yellow in color. These might have been the most durable, but suddenly weren't made anymore. I have a few pair in my collection. Sometimes, these come up for sale on ebay. Will be curious to hear what you think about the new ones when they come.
     

     

    Please register to disable this ad.

  7. brianjrealto

    brianjrealto Well-Known Member

    Messages:
    539
    Location:
    Dallas, TX
    I looked closely at the Heils to see the diaphragms. One has warped pleats in the center that tapers like the shape of a cats eye pupil. Mine do have the mesh. I'm still going to try the new phragms in comparison and will report back.
     
  8. brianjrealto

    brianjrealto Well-Known Member

    Messages:
    539
    Location:
    Dallas, TX
    Also, the warped diaphragm speaker doesn't sound as good as the other, close up. a bit of grainy/distortion presence.
     
  9. jcidave

    jcidave Member

    Messages:
    52
    Location:
    Williamsburg, VA
    When the diaphragm is overdriven, it overheats and the pleats start to stick together. Eventually they melt together. This could be happening in this case, so replacement seems like a good idea. This was probably started before your ownership.
     
  10. bimasta

    bimasta Super Member

    Messages:
    2,605
    Some of my diaphragms are failing (Great Heils). The wires are separating from the pleats, and they buzz on peaks. Unlistenable. It may be age, thus inevitable.

    However, I had a pair set up in the living room: one was exposed to direct sunlight through an open window for 2–3 hours a day. It was the one that failed; the other, in shade, is still fine. Draw your own conclusions...

    I'd love to read your assessment of the new replacements.
     
  11. brianjrealto

    brianjrealto Well-Known Member

    Messages:
    539
    Location:
    Dallas, TX
    Thanks Bimasta and JCDave..

    You got me thinking.. these speakers were in storage in their original boxes for about 25 years, said the previous owner. Sitting electronics is never good, best when used regularly. Although these were storred properly, the aging from non-use could have been a factor in this case, coupled with playing through them at periodic loud volumes through the aging original caps on the crossovers. my crossovers had the dreaded Mexican caps with black bodies and red tips..

    . Just hypothesizing...

    I’ll probably have the new phrams arrive soon and installed next week and will report back..
     

     

    Please register to disable this ad.

  12. bimasta

    bimasta Super Member

    Messages:
    2,605
    I imagine they'll change over time (the disputed "break-in" period). I'm very interested in out-of-the-box performance but a periodic update (if you have the time) would be more informative, more indicative of what they'll sound like for the next 30 years.
     
  13. brianjrealto

    brianjrealto Well-Known Member

    Messages:
    539
    Location:
    Dallas, TX
    Agreed... I assumed there would be some break-in. I would imagine 500 hours for reference with many changes along the way. Same thing happened with my Schiit Gungner taking 500 hours to mature, with the greatest changes occurring between 400 to 500 hours. Not the same gear, but most nice additions I've made new along the way always need break in before realizing their full potential.
     
  14. jcidave

    jcidave Member

    Messages:
    52
    Location:
    Williamsburg, VA
    When I was selling this product in the 70's, we were never advised of any break-in period. Nor have I seen anything written about it. Frankly, back then, none of the manufacturers that we carried mentioned breaking in their equipment. My AMT-3 diaphragms are 40 years old and sound fine. What failed are the foam surrounds on the woofers. But Everybody's foam woofer surrounds failed. So I've coated mine with butyl rubber. I will coat the surrounds on the refurb'd pair of AMT3's I'm expecting from my favorite west coast seller in a couple of weeks. If there is any difference in sound after coating, I can't hear it.
     
  15. brianjrealto

    brianjrealto Well-Known Member

    Messages:
    539
    Location:
    Dallas, TX
    The new Diaphragms arrived yesterday.. I'll replace one and compare for a day or so, then replace the other. I'll test the resistance and compare between the old and new and post results. I'll have pics uploaded of the old diaphragm and post it once it's removed.

    I'll replace the one either tonight or tomorrow... I hope there isn't needed break-in and they sound fantastic out of the box
     
  16. brianjrealto

    brianjrealto Well-Known Member

    Messages:
    539
    Location:
    Dallas, TX
    Stupid questions time... making sure I do this right..

    See pic below as an example..

    1) Once I loosen the 2 bolts, does the Heil remove easily?
    2) the diaphragm wires run into the white/red "junction" on the back of the Heil. How do I disconnect the diaphragm wires from this?
    3) is the Heil set in a plastic shell casing? I can't tell from this photo, but it looks as though there is a casing.
     

    Attached Files:

     

    Please register to disable this ad.

  17. jcidave

    jcidave Member

    Messages:
    52
    Location:
    Williamsburg, VA
    Looks like you removed the Heil from the speaker with no problem. Once you remove the warranty tape and expose the top of the diaphragm slot, there are probably 2 dabs of putty on either end on the dia frame, just remove those and push down on the dia frame with your finger or a screwdriver. you will be able to grab the dia frame from the bottom. push down on the spring loaded red buttons on the white terminal box to release the wires. don't ever pull on the wires or put any tension on them as they are attached to the dia frame. the dia frame may have a red dot on one side. I would reinsert the new dia frame with the red dot to the front of the heil case. push down on the red buttons and hold down while you reinsert the 2 dia wires. that should be it.
     
    BilboBaggins likes this.
  18. BilboBaggins

    BilboBaggins AK Subscriber Subscriber

    Messages:
    3,309
    Location:
    Ottawa, Canada
    I think there was a seal on mine when I removed it. That might be why it doesn’t lift up. Try just putting enough pressure on one edge so it breaks the seal. Other than that, what jcidave said.
     
  19. brianjrealto

    brianjrealto Well-Known Member

    Messages:
    539
    Location:
    Dallas, TX
    So, I replaced the Diaphragms last night. Upon start of the work, I noticed that these phragms have been replaced before.

    One of the speakers' Heils was a headache. Overall, they sound much better now, more dynamic and unveiled.

    One Phragm was in rough shape upon inspection when removed from the "bad" speaker. The pleats were bent and some separated from the substrate glue. This Heil was also separated in halves due to the plastic frame broken at the center seems- the plastic frame of each triangle side is glued to the other at the center top and bottom. Before loosening the 2 bolts, I noticed that the Heil had a 1/4" space gap at the bottom of the plastic frame, while the top of the frame was seamless and no gaps. So, this Heil had been previously bolted down already separated by that 1/4" inch at the bottom of the frame, and I now understand why.... Once I began removing the bolts, I quickly realized the Heil frame was broken and began to separate.

    Here's some advice if you have a broken frame on a Heil since I;ve already been through this and managed to get the Heil together and working again...
    Getting the 2 halves back together was impossible by hand as the magnet polarity "pushes" each Heil Half away from each other. Thats why there was that 1/4 inch gap at the bottom of the frame from previous changing of the diaphragm.

    Guidance:
    Bolt down on one of the Heil Halves to the speaker cabinet. This holds the Half in place while attaching the other Heil half and screwing the 2nd Heil half bolt down.
    Hardware needed from the Depot:- a home-made "vice" is in order here using 2 long 8" bolts, 2 metal brackets and 2 wingnuts. I constructed the "vice" around the Heil and torqued the wingnuts until the bottom frame gap disappeared. You have to loosen slightly one bolt while torquing the vice. This process worked out great bringing the halves together and eliminating the 1/4" frame gap from before.

    also... to do this process, the Heil will be upside down so you can slide the new Diaphragm in after joining the broken halves to the cabinet. Again, the Magnet polarity is pushing the halves apart from each other, so I couldn't find a way to marry the halves before installing the 2 bolts with the Heil in the correct upright position and new Diaphragm in place. Maybe 2 "vices" would have worked, but the upside down approach didn't bother me as these Heil's are Di-pole anyway.


    The 2nd speaker Heil frame was fine and not separated at the center seams. easy to replace the Diaphragm

    all in all, I'm very happy with the improvement in sound. Well worth swapping out for new diaphragms!
     
  20. toddalin

    toddalin Super Member

    Messages:
    2,219
    I've seen lots of Heils split in half. I am wondering if people are trying to store them without the two bolts holding them together/in place and over time the action of the magnets takes its toll.

    BTW, the bolt holes have a spacing of 102mm. If you ask ESS Heil, they'll tell you/told me that it is 100mm. :rolleyes:
     

Share This Page