This dynamic microphone amplifier circuit has a total gain of 200 times. If we use 200Ω microphones R4 must be 220Ω and C1 is 4.7uF. If you want the to get the lowest noise signal from this dynamic ...

The microphone preamplifier circuit design presented in this schematic use SSM2015 produced by Precision Monolithics Inc. (PMI) which offers a high amplification and low noise ( 1.3nV/√f). Has been ...