Reproduction Kappa Polydome Diaphragm Demand?

Discussion in 'Infinity Loudspeakers' started by Bobbyd38, Jan 31, 2018.

  1. Bobbyd38

    Bobbyd38 AK Subscriber Subscriber

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    Having purchased several Kappa systems and experienced the ultimate Polydome failure. I am seriously considering contracting a firm to replicate, as close as possible in performance and cosmetics, the 3” Infinity Polydome diaphragms.
    Obviously this may be a sizable investment in tooling and engineering, and I’m trying to get a feel for what the demand would be and if this endeavor would be worth it? What would you pay (for the part) to have accurately produced Polydomes? Not Silicone, or Dust caps!
    Do you think there would be enough interest in these, it would be a worthy investment?
    Anyone have any idea how many systems were produced with these Midrange drivers that are doomed to fail?
    Thanks, Bob
     
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  2. simplynuts

    simplynuts Active Member

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    I have a friend and a fellow aker in PA that has millersound rebuild these I believe.
     
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  3. Bobbyd38

    Bobbyd38 AK Subscriber Subscriber

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    I’m familiar with Millersound and I here they do fantastic work too! However when they restore the Polydomes, because there is no direct replacement for the Poly Diaphragm, they use a Woofer Dust Cap as a substitute. I understand sonically they’re close to the original, but a few mods to the cab are recommended (modifying the original Infinity design). The positive is, it allows these incredible speakers to continue being enjoyed, BUT visually it is not an accurate restoration! Kappa’s are Vintage audio history and should be preserved in their original glory! I want to replicate the original Polydomes both Sonically and Visually! In fact, I could be a supplier for Millersound, with their mechanical expertise the Infinity Kappa Series speakers could be restored to original condition 100%!
     
  4. Infinity!

    Infinity! Active Member

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    422
    If you're talking about the original polydome k's, (used in the original Kappa series) AND if you're talking about a near perfect (if not completely perfect) reproduction, I might pay around $400 for a pair.

    Edit: Wait, do you mean just a new dome or a whole new driver?
     
    Last edited: Feb 1, 2018
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  5. slimpikkins

    slimpikkins Super Member

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    I'm not sure how many speakers are out there. Sure we are into the hobby and have a place to chat about it but we are few and a few of us have Infinity speakers. I don't think it will be economically for you to do it. Tooling is very expensive. I work in a machine shop and our shop rate is around $125 per hour last time I check. Also design, r and d on materials will all be big bucks for selling a few units.
    There was a man in Australia named Graz who makes the Emim diaphragms. While he was making them there was much excitement then the price came and many complained. His are expensive and I know for a fact he is not making much money and sold a few hundred pairs. (I bought 3pair and they are freakin amazing...). Most guys who fool around with 30-40 year old speakers do it for fun, are cheapskates plain and simple, or poor audiophiles (I am both). We'd just by new if we were not...
    Jim
     
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  6. Archguy

    Archguy Official Roiurama Factory Rep Subscriber

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    I bid $200 !

    Oh yeah. Sort of like that.

    Well, I do buy new but I also like vintage. There's something about serious accomplishment in any field that's worth preserving and celebrating, even or especially many years after the fact. At any rate my Kappas are totally competitive with several different brands of new speakers I've bought in the past few months. Both sonically and in the solidity of their construction.
     

     

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  7. qguy

    qguy Super Member

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    What is the possibility of getting the original equipment and use the same material to make new ones ?
     
  8. whoaru99

    whoaru99 Epic Member

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    I think a question in this case is, if there was money to be made, would someone already be doing it?
     
  9. okeeteekid

    okeeteekid Well-Known Member

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    764
    Location:
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    All you need to make is the dome/voice coil assembly like the original picture below, when you disassemble the original removing the 4 screws the dome assembly is easily removed and replaced, no sense making the whole driver as you would then have to make two different units, one for the original kappa series and one for the series II, If you make just the full dome assembly as pictured below buyers could easily drop it right in both kappa series speakers and it would cost less for you to make and less for buyers to purchase = more $$ in the end, (pic from the net).
    14.jpg
     
    Last edited: Feb 1, 2018
  10. swechsler

    swechsler Frog Whisperer

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    I'd say almost nil. First you have to figure out the manufacturer, then you have to hope that they still have the original forms (remember that these were last made about 25 years ago). But even if you get through that, there are almost definitely agreements in place between the manufacturer and Infinity that prevent them from providing the equipment to anyone, or even manufacturing them for someone other than Infinity (I will point you to this lawsuit from several years ago)..
     
  11. Infinity!

    Infinity! Active Member

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    If they are JUST the dome, i agree $200. If it's a whole driver replacement, i'd pay around $300-400 IF they sound that amazing!
     

     

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  12. okeeteekid

    okeeteekid Well-Known Member

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    When infinity sold just the dome they were $60.00 the whole driver was $120 in the 90's, I bought two domes for $120 plus shipping but that was back in the 90's when they were plentiful.
     
  13. swechsler

    swechsler Frog Whisperer

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    I assume you mean the entire diaphragm - dome + voice coil + mounting, right? I can't imagine they sold the dome by itself.
     
  14. Archguy

    Archguy Official Roiurama Factory Rep Subscriber

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    Good job! Since I didn't get mine until last year, I didn't have the benefit of such foresight.
     
  15. okeeteekid

    okeeteekid Well-Known Member

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    Location:
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    Just like you see in the pic in my post, you just had to remove the 4 screws, lift out the old dome and drop the new one in, they also sold the complete speaker.
     
  16. Bobbyd38

    Bobbyd38 AK Subscriber Subscriber

    Messages:
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    I don't intend to make the whole driver or even the voice coil, just the diaphragm. I think using a Woofer dust Cap as a substitution is a good work-around, but it's certainly not a solution to restoring to original. The diaphragm is what fails. With an alignment jig, you can repurpose the the voice coil and all the other parts, use the proper adhesive, and reassemble. Someone is selling Silicone versions on eBay, and they FAIL miserably! Why, because silicone does not adhere to ANYTHING!
     

     

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  17. Bobbyd38

    Bobbyd38 AK Subscriber Subscriber

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    I plan to replicate one part, the Diaphragm, Infinity (or whats left of it) has shown no interest in supporting a 30 year old archived product, I highly doubt there would be any benefit to defending the Patent! I'm not building Kappa 8' clones! I'm simply a preservationist trying to find a solution to a poorly design component that fails and renders a great product useless, that is unless you want to glue a Woofer Dust Cap to it, and Mickey Mouse a solution that looks nothing like the original? Tooling should be minimal for one component, getting the material correct is key, and I certainly don't plan to use Silicone, which does not adhere to anything, especially VOICE COILS, like someone that is selling them for $150 a pair on eBay, and ripping people off!
     
  18. Bobbyd38

    Bobbyd38 AK Subscriber Subscriber

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    No, just the Diaphragm, The diaphragm is what fails. With an alignment jig, you can repurpose the the voice coil and all the other parts, use the proper adhesive, and reassemble.
     
  19. goodolpg

    goodolpg Just an old fart trying to help. Subscriber


    Good luck, hope it works out for you.
    Lots were made, many failed, many are long gone, many people will never know if you succeed and make the product that you hope to make.
    Kind of a long way of saying IMO it will be a limited market at best, but those who do know and want the product will be very pleased with your efforts should you succeed and can market them "affordably".
    EDIT-- If you could get them into repair shops or parts supply places that could help build your exposure and sales. There's a couple people on ebay who do "rebuilds" who might be interested. Or offer them there yourself.

    I'm a painter by trade...I HATE when I'm prepping to paint something and I see silicone caulk was used for whatever reason (like around sinks, showers, or kitchen back splashes).
    Very few products will stick to it and without overcoating it with something (oil base Kilz works sometimes, sometimes I just go over it with latex caulk and hope it completely covers the silicone caulk and sticks) any paint applied will separate and spiderweb.
     
    Last edited: Feb 2, 2018
  20. slimpikkins

    slimpikkins Super Member

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    My "Mickey Mouse" fixes work pretty good and kept a few pairs of speakers from the land fill or eBay parts lots. I'd call that preservation. They cost about 25bucks to fix and sound very good. Mounting the dome to the vc is not for the faint of heart. The original dome, surround, and vc are all one complete unit and were not glued together but made together to my knowledge. It's a shame the originals are mostly toast they did last a long time.
     
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