It's interesting to see by the Gefell M300 frequency response curve that while the microphone is a cardioid type, it does not exhibit the typical proximity effect bass boost. Rather, the mic actually shows a very gradual bass roll-off below 100 Hz. See below link for some review comments and the frequency response curve.
http://recordinghacks.com/microphone...ch-Gefell/M300
Like just about all condenser mics, the mic shows a slight treble rise, but in the case of the Gefell M300 design, the rise is very gradual above about 2 KHz and not peaky at all.
- Glenn