R/E/P Community
R/E/P => Klaus Heyne's Mic Lab => Topic started by: RuudNL on July 04, 2022, 05:38:12 AM
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Last week I repaired a Neumann CMV563 (M7S capsule head).
I couldn't resist to look at the condition of the M7 capsule and this is what I saw.
What could be the cause of the strange discoloration?
Under normal conditions, gold does not oxidize.
Is there maybe a reaction with another metal?
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You got it!
Corona oxidization- starting from the center lead-out and gradually going outwards - is caused by the electro-chemical interaction between polarization voltage and the metal alloy used in the conductive sputtering of the capsule.
The oxidization was again a problem during the first few years of the 1970s, then was forever eliminated by changing the formula.
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I have nothing to contribute to the question but I do have to say:
There is something incredibly beautiful about the way those m7 were constructed.
Even though i have to look past the obvious issues with this particular capsule, it blows my mind that they could build something so precisely using glue to secure the diaphragm at its edges.
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Oh interesting, does it affect the sound at some point?
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Depending on the severity of theCorona oxidization, and extent of the area affected, it will affect the sound - from increased noise floor to total failure.