Ideal material for ribbon mic baffle

[Dylan W]

I'm experimenting with a pair of cheap Chinese ribbons I have. One of the things I'd like to try is extending a baffle around the ribbon motor to increase LF extension, ala the Coles 4038.

The BBC Monograph from which the Coles is derived refers to "closely woven gauze," later specifying further a "a single layer of bolting cloth supported by a coarse wire mesh": https://downloads.bbc.co.uk/rd/pubs/archive/pdffiles/monographs/bbc_monograph_04.pdf

The original Harry Olson patent suggests a "fine silk mesh": https://patentimages.storage.googleapis.com/b5/60/f1/d0147ef61c707c/US2348356.pdf

I'm not sure how to find fabric with the right impedance. There are a number of different types of fabric available.. silk and nylon meshes with various hole sizes, in addition to metal "bolting cloth." (I think the "bolting cloth" in the BBC pdf refers to a fabric bolting cloth though.)

I suppose trial and error is a simple way to figure it out, though I'm not sure how to accurately measure LF with the equipment I have. I'm considering building a "motional impedance bridge" as per the BBC monograph.

Has anyone trodden this ground already?

 

[12afael]

I went to the rabbit hole of meshes for beyer ribbon mics. I never ending buying the stuff but i saved this provider in ebay https://www.ebay.de/itm/261836344201?var=561166889531 there is several provider for copper mesh with different hole sizes. not exactly the same as cloth but if you want to experiment...

 

[Rud]

I've been looking for this too and nylon food-safe filter mesh can be great because you can get 5 different hole openings and experiment with the impedance variance. I found for pop filters that an air-gap between different mesh size helps more, but that's different from what you're trying to accomplish.