Well yeah, you need to figure two things: 1) diaphragm dumping, which depends on the blind hole size and depth and determines flattness of the response, and 2) acoustical labyrinth parameters, which besides affecting the dumping also determine pattern control tightness. Very often those two contradict each other...
In API Microphone Handbook there is a math for simple stiffness controlled omni capsules. Even for such a simple and straightforward system the math is... say, not for a usual sane people, and has rather academic interest.
AFAIK, all the studio condenser capsules were made empirically, starting with a rough estimate, and then painstakingly micron by micron changing parameters and evaluating until getting the things right, both freq. response and pattern.
Every micron is of essense, so besides lots of patience you need high precision machinery. My lathe has digital readout system with 1 micron resolution. I spent about 3 full weeks just for setting it up, alone. To reduce vibrations it is bolted to a huge concrete pedestal table and the motor mounted separately (also bolted to the table, not to the lathe). They only interact through a special chain belt, which additionally reduces vibrations. The motor puley is machined right in the system, to reduce runout.
Everything is tight, parallel, and perpendicular with high precision, using Mitutoyo 1 micron resolution dials. I am still working on it.
Then you will need some means to measure freq. response...
Best, M
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