Turning a Sennheiser MKE10 into a PZM

[TromNek]

Thanks all
Yes, I can derive the measurements from both those figures.

I searched for the research paper you referenced but couldn't find anything.
Can you share a link to it please.
I'd like to understand more of what their analyses showed.

 

[k brown]

Here's the Neumann AES paper.

At one point I actually made my own SASS-B type mic using the spiral boundaries. Unfortunately it looked like a couple of huge pinnae.

 

[TromNek]

Thanks so much for the paper. It has some very pertinent information.
From reading it, I see now that a larger 1,2m x 1,2m plate is not good.

I think I'll start with the GFM triangle made out of MDF or Hardboard .
Later try a spiral version.

I would have liked to see some more discussion of how they 'calculated' the dimension needed for the triangle and spiral.
They discuss the minimum size needed for half wave length of the lowest frequency desired. But that is for regular shaped object.

Perhaps for an irregular shaped plate (GFM Triangle or Spiral), you would use the maximum distance across the plate passing through the center of the microphone to calculate the lowest frequency.

 

[k brown]

This'll give you all the deets on boundary sizes regarding shelf frequencies, and much more.

 

[TromNek]

Very nice. Thanks so much.