AKG C 414 EB capsule repair: searching for DIY suggestions

[frobozz]

Hi everybody, I just dismounted this bad working capsule and I found that the backplate was sitting on a orange foam that vanished being aged.
Any suggestions for a DIY replacement or any chance for a spare?
Thank you very much!

 

[bremusound]

Someone else had the same problem and found a way to fix it

https://groupdiy.com/threads/akg-ck12-teflon-repair-and-surprise.75161/

 

[soliloqueen]

i would suggest getting new foam cut out of a foam that won't disintegrate under these conditions, like crosslinked polyethylene

 

[frobozz]

I did as suggested now I’m going to test

 

[soliloqueen]

I did as suggested now I’m going to test

this looks like polyurethane foam, which will only last a few years. it also may not be dense enough, be careful

 

[frobozz]

this looks like polyurethane foam, which will only last a few years. it also may not be dense enough, be careful

Thank you but I don't have knowledge on foam... any idea on where I can cut a small piece of a better foam? my coach or pillow maybe

 

[soliloqueen]

Thank you but I don't have knowledge on foam... any idea on where I can cut a small piece of a better foam? my coach or pillow maybe

What's your address? I might be able to send you some that could work

 

[Icantthinkofaname]

i would suggest getting new foam cut out of a foam that won't disintegrate under these conditions, like crosslinked polyethylene

Would they be able to use something like EVA foam from a crafts store?

 

[soliloqueen]

Would they be able to use something like EVA foam from a crafts store?

possibly, but i'm not sure about the density there. they could try it

 

[HerbertR]

I would suggest contacting the "microphone doctor" Michael Amon from Vienna, Austria. In my opinion he is the best known microphone specialist on the market and a former AKG Employee / Engineer. https://en.mikrofonservice.at/
He is also on Facebook and here in the Forum under MSVienna or so....

 

[Paul W]

Would they be able to use something like EVA foam from a crafts store?

EVA foam is generally closed-cell foam. The black foam in the above pictures looks like open-cell (sponge-like) foam. I wonder what the original foam was, and whether it's supposed to seal like a gasket (in which case you want closed cell) or NOT seal, like a sponge.

OT but I discovered you can vacuum form EVA foam. (And you can vacuum form with a toaster oven to heat the foam, a vacuum cleaner, a board with a hole in it, and a mold of some sort.) I'm wondering if that might be useful for making soft mic domes or suspensions or something.

 

[Tim Campbell]

From what I remember it is more like compressed felt or paper than foam. Any foam should work. The chamber depth is set by the plastic it presses the membrane against.

 

[k brown]

In that case, I'm wondering if a loop of the right thickness of yarn might be easier to deal with than cutting a ring of foam.

 

[bremusound]

Here’s the dimensions of the ring:

outer diameter 29mm
inner diameter 25mm