John, thanks for chiming in! Your comment actually pertains to the ORIGINAL QUESTION:
What is the sonic difference between the M930 (cardioid only) & the UM930 (multi-pattern), when both mics are set to cardioid?
You can get into technical-physical aspects if you have to.
So, the multi-pattern version has a completely separated (entire) capsule. I guess it is "disconnected?"
when set to Cardioid ... but there must be some type of different vibrations going on that would make it sound different than its single capsule version?
(Hopefully the question is clearer now for Klaus & he can give his input.)