Hey, in this graph im attaching here is showing that if one do a 1 to 1 input impedance to output impedance of a dynamic microphone and an mic pre amp the low and high frequency response of the mic is reduced but the middle frequencies stay intact....

I would like to understand why just low and high frequencies get affected but not the mid ones????

 

possibly because of loading on the windings in the microphone. less load with a much higher impedance. current load affects the mechanical load on the diaphram