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

 

[Hansblooey Ribbon]

Anyone in the states repair these capsules?

 

[Tim Campbell]

Repairing this capsule might cost more than finding a replacement.

 

[Hansblooey Ribbon]

The capsule went bad many years ago, removed and somehow I lost the body. If I could get it back into shape for under $300 and use it for a “C12” I’d be happy with that.

 

[Tim Campbell]

The capsule went bad many years ago, removed and somehow I lost the body. If I could get it back into shape for under $300 and use it for a “C12” I’d be happy with that.

When new these capsules used to cost 200 USD. You could probably find a used one for cheaper than a repair.

 

[Hansblooey Ribbon]

We’re talking about the brass and machine screws capsule?

 

[Tim Campbell]

We’re talking about the brass and machine screws capsule?

No, we are discussing this nylon capsule the OP is trying to repair. I am sure there are plenty of them out there on the used market because people replace them often with modern "brass" versions. You could also just replace it with one of the "brass" versions out there.