New Glass Diaphragms (origin of Edison Diaphragms)

[Phonoboy]

Interesting stuff. Thanks.

[edisonphonoworks]

I have tested a few of these diaphragms in the studio recorder. When recording with glass diaphragms remember this, the thicker, the diaphragm, the better the high frequency response is going to be, however it is not going to be as sensitive. An 8 thousandths records with clarity and detail however the instruments, singers or speakers must be somewhat loud. I have tested 6.5, 7, and 8.5 diaphragms. (for size .0065" thick.) the 6.5 is very sensitive, but very bassy, similar in sound to most Columbia moulded wax cylinder recordings. I have used an 8 ½ for a long time, as that is what the thickness of what is sold to collectors as " new glass diaphragms" , they do have great clarity on the top however not that sensitive for soft recording subjets. I would say the .0075-.007 sizes is a good happy medium for most recording, it has a good deal of clarity, but yet has warmth, records sibilants, and has a deal of presence. I will say that trying to compare a .002 mica and a glass diaphragm is like apples and oranges density must be very different a .008 mica diaphragm if used for recording would end up having a whole lot of well, nothing, it would be a very faint thin recording, while an .008" glass diaphragm is much louder and clearer. A .007 glass is much more sensitive and records a louder signal than a .002 mica.
With the .0075 I get a loud recording standing about 4 inches from the horn, talking with clear annunciation but speaking in a normal, informal manner, if you get closer,and speak in the loud tone, you would for a home recorder, you will get a very loud, and it will echo as it cuts deeper and into the adjacent groove. Soft instruments, like a violin, however will record with the thinner diaphragms. for added clarity to the thin diaphragms using some beeswax on the top gasket covering the edge, would increase high frequency clarity with the think diaphragms.

[edisonphonoworks]

Mr. Gordon, did you receive your glass diaphragms and have you used any?