Matrixmusic wrote:
Does that mean that Earthworks M550's are no good on the bottom end?
Freq resp 9 Hz - 40kHz +1

This could be true, but I find it very hard to believe that the mic can
pick up 9hz or even 20hz, only 1 db down from 100hz.

Sure--measurement mics (including Earthworks) do this all the time.
Even a 1/4" capsule can do the job (albeit a little noisily.)