Edison Model C reproducer question

[howardpgh]

What type of diaphragm is supposed be in this unit? Mica/Metal/Glass?
I have a several Cs and they seem different.

[Phonofreak]

The earliest ones used mica. The later ones used a copper diaphragm. If this is for your Model B, then copper is the correct choice.
Harvey Kravitz

[phonojim]

Since it's not difficult to change diaphragms in those reproducers you could try both and see which type sounds best to you. Personally I prefer the sound of the copper ones.

Jim

[De Soto Frank]

Is there an approximate serial number range of which uses what type diaphragm ?