Don Romano (alt)
1 meter on-axis, 1 meter off-axis and 20 centimeter on-axis response for the microphone array I'm working on. My simulator now displays the array itself (see the bottom right graph).
I think I've found a clever way of using 3 microphones, delays and crossover filters to get a near-optimal cardioid polar pattern at all frequencies without getting a comb filter at high frequencies or needing insane EQ gain levels to flatten the frequency response.
Don Romano (alt)
The technique is basically to keep the front microphone untouched, using a high-pass filter on the microphone right behind it, and a low-pass filter tuned to the same frequency on the rear microphone. I'm effectively combining two different cardioid microphones — where one is tuned for low frequencies and the other is tuned for high frequencies — and then gluing them together with a crossover filter. The result isn't flat, but it needs a lot less parametric EQ gain than my previous design.
Don Romano (alt)
Oh, and a full history of what I've posted on the subject of MEMS microphone arrays can be found here:
https://polymorph.no/cardioid-mems-microphone-array/
(This is the third post in a thread. Expand it to see the context.)
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