High Energy L-EMIM (aka Epsilon version)

Discussion in 'Infinity Loudspeakers' started by soundofvoid, Aug 12, 2013.

  1. soundofvoid

    soundofvoid New Member

    Messages:
    42
    I have a problem with one of my Epsilon L-EMIMs.
    During transportation one L-EMIM got hit (slightly).
    As a result, a magnet (one only) detached,scratched the foil (without tearing it!), hit an aside magnet and broke.
    The foil is dead and needs replacement.
    A friend of mine is in the etching business and will make me a new one (plus some more for spares), since Infinity doesn't stock them any more.
    It's a good thing that EPSILON white paper describes exactly how it is made!
    My real problem is the magnet...
    It is black,it doesn't corrode on surface,doesn't look to have any coating.
    I have sources to make me a magnet with the same dimensions but i need to know what type of magnet this is!
    Is it ceramic (what type?), samarium cobalt or neodymium (again what type N42 N45 etc etc)...
    Anyone knows any details on the subject or has any "inside" info about this?
    Wanna be be a lifesaver?
     

    Attached Files:

     

    Please register to disable this ad.

  2. okeeteekid

    okeeteekid Well-Known Member

    Messages:
    801
    Location:
    Northern NJ
    Sorry i don't know what the magnets are made of, it's a shame that infinity doesn't support any of their products, i had the Mts prelude still under warranty and one of the midrange drivers went bad and they told me that the parts are no longer available but they would search for a used one for me lol, you're lucky if your friend can make you a new diaphragm, if i were you i would have him make you two of them and replace them in both speakers so that they sound the same, best of luck.
     
  3. Maxamillion

    Maxamillion Super Member

    Messages:
    1,340
    Location:
    New Jersey, USA
    They are samarium cobalt. Neodymium magnets have a shiny nickel coating to help prevent oxidation.
     
  4. soundofvoid

    soundofvoid New Member

    Messages:
    42
    That is my best bet too.
    Although not all neo magnets are nickel coated...
    I have ordered in the past ring ones with epoxy coating
    for a levitated turntable spindle and they came in ordinary black...
    But these really look naked and are coarse around the edges...not smooth like the coated neos...
    I will make the order for samarium cobalt and see what happens...
    Come to think of it...if i have the magnets and the foils, the rest is easy...
    I can make me as many units as i like...
     
  5. StimpyWan

    StimpyWan AK Subscriber Subscriber

    Messages:
    3,962
    Location:
    Blue Ridge Mountains!
    Any chance that the L-EMIM foil can be repaired? Since the foil isn't ripped, I wonder if a signal trace didn't get torn instead? There's a tutorial on the old Bobby Shred site, on how to repair EMIT's; the same thing should be able to work for a L-EMIM...

    http://www.bobbyshred.com/infinity/emit.html

     
  6. okeeteekid

    okeeteekid Well-Known Member

    Messages:
    801
    Location:
    Northern NJ

     

    Please register to disable this ad.

  7. okeeteekid

    okeeteekid Well-Known Member

    Messages:
    801
    Location:
    Northern NJ
    Can you post some pics of the damage done to the foil/diaphragm
     
  8. soundofvoid

    soundofvoid New Member

    Messages:
    42
    I have thought of it but it is beyond repair...
    Many traces have been damaged...their distance is that of a human hair...
    and i'm really not interested since i can have me a pristine copy...
    The foil was never my problem...the magnet is.
     
  9. okeeteekid

    okeeteekid Well-Known Member

    Messages:
    801
    Location:
    Northern NJ
    You know they added an extra backing/layer to the kapton to absorb up the coloration that the driver adds, the older style L-emim's didn't have this backing, wish you luck finding out what that backing material was made of.
     
  10. okeeteekid

    okeeteekid Well-Known Member

    Messages:
    801
    Location:
    Northern NJ
    They can probably still be repaired as that's not that far of a gap.
     
  11. soundofvoid

    soundofvoid New Member

    Messages:
    42
    I will try...
    But regarding the foil construction i would not hold my breath regarding the materials
    behind it...
    They just added another layer of kapton with pressure sensitive adhesive to get the exact weight they needed to "tune" the speaker.
    Which is what i will try to do too...
     

     

    Please register to disable this ad.

  12. PSHIM

    PSHIM New Member

    Messages:
    1
    If those magnets were Samarium Cobalt or Neodymium Boron Iron you would need a huge press to assemble and disassemble the plates as the opposing force would be too great to manage casually. They are probably Ceramic 8 magnets like the IRS Beta's L-EMIM.
    How did you make out on the new diapharams; are the originals double sided circuit traces with soldered plated though hole to connect from side to side or like the old EMIMs or is it just single sided traces under the back Kapton cover sheet?
     
  13. soundofvoid

    soundofvoid New Member

    Messages:
    42
    Sorry PSHIM i didn't answer fast enough.
    I have a couple turntable projects on the way that absorb all my time...
    Yes some kind of jig will have to be used to put them back together.
    I have constructed something like that in the past to open up and close a Quadral XX-500 midrange that has neodymium magnets...(see the pics that i think speak better than words)
    You can make a dead simple one with some pieces of wood that will guide the exact opposition of the two parts and you can easily press them together by screwing down
    the bolts ... a little more each time all around.
    The exact construction of the foil (along with actual data of thicknesses) is in Epsilon white pater that can be found easily in the e-cloud.
    From what i see it's a one sided etching job but the final diaphragm is pretty robust-thick!
    Probably because of the two layers of the kapton and the adhesive layer between them.All i can say is that it looks much less susceptible to wrinkle than the old L-EMIM!Somebody has learnt his lesson there!
    The connectors are the tough part: one side travels with a soldered wire about 5 cm long to the actual hooking post and the other is with a shorter 1 cm wire.
    The are both rivet-pinned down to the plastic frame with a bit of leeway...
     

    Attached Files:

  14. okeeteekid

    okeeteekid Well-Known Member

    Messages:
    801
    Location:
    Northern NJ
    No mention of removing and replacing/ repairing the flakey pealing neodymium magnets
     
  15. Guest124

    Guest124 Member

    Messages:
    85
    Location:
    Australia
    Graz can refurbish (replace the ribbon panel) on L-EMIM drivers if required. I'm unsure of price, though fyi replacement Emim panels cost $235USD for small quantities. Also, Graz informed me that there are magnet kits for sale on Ebay fyi. And if expert help is needed to do the repair, he works with an Apogee Installer - Repairer who has done some complete refurbishments including magnet replacement. You can see further details in the Emim thread I just posted - http://audiokarma.org/forums/index.php?threads/graz-emims-update.836694/
     
    Last edited: Sep 7, 2018

Share This Page