Thiel Owners

I think I may have found something here. Maybe someone could take a look and see if this could be the original mid for the 3.5, Scanspeak 13M/8640 . Here is a link to the spec sheet, https://www.scan-speak.dk/datasheet/archive/13m-8640-00.pdf
Or, this version, 13M/8636 with kevlar cone as opposed to paper in the 8640 linked above.  http://www.scan-speak.dk/datasheet/archive/13m-8636-00.pdf

Unfortunately I’m at the beginning of my learning curve, so maybe someone could chime in with an informed perspective. Thanks

They were paper cone, not kevlar.

Bluetone - Please pursue this 3.5 midrange matter. Make a chart of the # and parameters original driver and the various replacements. As ketchup says the original cone was paper. Kevlar is "better", but its resonances would be different plus it gives up 1dB of sensitivity to the 8640. For perspective, we must find something very close to the original because the whole speaker system (enclosure, xo, other drivers, etc.) works together and changing any parameter of the midrange driver requires re-engineering the xo. That is a possibility as long as most of the parameters match and the ones that don't match are friendly.

This investigation would make lots of people happy. It is not on my current list because of its scope and competing priorities.
Keep up the good work. - Tom

Tom, will do.  I'll post the analysis on my website, which I will link to once I complete it.  

The original 3.5’s mids had paper surrounds.