The Talking Machine Forum — For All Antique Phonographs & Recordings

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

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

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

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