The Talking Machine Forum — For All Antique Phonographs & Recordings

Our workshop has procured a stamper for making Orthophonic diaphragms, and to our knowledge this is the only fully machined metal stamper in existence. As shown in the photo below, I am experimenting and developing a new method for stamping these than the method used in the recent past by Lee Kirk. Lee used a 2-stamper system, and at times this developed unwanted creases in the final diaphragm. I am hoping to use a 2-stage system as well, but the first stage will be low pressure pneumatic, similar to hydroforming, using a thin rubber membrane to start the forming of the duralumin alloy foil in the “right directions” before the physical final stamping. Full hydroforming can not be used, or rather, a method has not been developed to utilize it fully because of the extremely thin foil: .0014-.0016” thin.

I am hoping to make these available in late 2020.

Very interesting Wyatt. It reminds me a lot of the HF compression diaphragm in my Altec Lansing 604-8G's. Just mount a voice coil.

Cool stuff, for sure!

I’m in the market for a couple ortho rebuildings. Can’t wait.

Great news. I look forward to their availability.

Nice. I appreciate your efforts in keeping machines sounding great!!
Ken

Looks great! I’m eager to see the final result.