... though that may be unrelated to the metal used in sputtering.
And I can’t imagine a better conductor than gold.
(...) If you heat up a mylar diaphragm it loses its tension (even permanent from some temperature point on) and comes closer to the backplate, thus increasing the mic's sensitivity.
Platinum also might be a good choice but I never heard of anyone trying it.
Pretty sure that's wrong. A Mylar film will actually tighten up with the application of heat.
Gold was selected because it resists any form of corrosion. Silver could possible work better if it didn't oxidize. Platinum also might be a good choice but I never heard of anyone trying it.
The Chandler REDD mics have platinum capsules.
So, the Chinese are now able to makle a large platinum diaphragm that sounds good and lasts? Would love to hear that mic.