AKG CK12 Teflon Repair and surprise

[VanguardAudioLabs]

I purchased it new in the mid-late 90's, so I know it hasn't been serviced. Seems like it doesn't involve invasive surgery to take a look though. I'll put it on my list to take a peek.

The things to watch out for:

1) getting the diaphragm off w/o damaging the teflon or the diaphragm itself. Remove the diaphragm post and put a 10mm M1 screw in its place, ideally with a hex head or other non-slip head. screw it in and it will pop the diaphragm out. Thanks to Dave Wheeler for the tip on that one.
2) getting any contaminants on the capsule, backplate, etc.
3) losing, bending, or contaminating the spacer ring between the diaphragm and backplate.

Easier way to check - inspect one diaphragm for tents. Then hold the capsule one diaphragm facing down and give it a decent shake-a-roo. gently use the diaphragm post to rotate the diaphragm and see if any new tents appear. If they do, then the foam inside is likely disintegrating and should be replaced. Cleaning everything thoroughly before reassembling is super important, those wee bits of yellowish foam can be nearly invisible.

 

[Double G]

That is correct. i recently worked on a C24 gen1 that had Teflon capsules in it from an AKG repair in which the brass capsules were found to be the issue.


I will say that capsule being equal, i prefer the C414EB-P48 version to the C414EB. P48 is underrated; i think people prize the EB because it was the last version to use the brass CK12 (although not all of them did; I think they transitioned to the Teflon CK12 sometime during the EB.)

Although the pattern switch on the P48 is an odd component that they only ever used for the P48.


That's correct. I think at some point AKG realized the foam they used early on was degrading. I'm curious to know which version of the standard Teflon capsule (0001 thru 0005, not the TLii which is 0009) they switched over to the new foam as well.

I ordered some 1mm adhesive foam sheets and they'll go on the laser cutter next week for future repairs.

That's funny because the other day I saw someone selling a EB P48 on reverb with a Beezneez CK12 in it. The seller listed all the reasons why the P48 circuitry is better than the EB.

What could be expected if a TLII capsule was put into an EB or EB P48?

Also could the capsules simply be swapped or would additional things need to be done to the circuitry?