ITEM NAME:GY-4466 Microphone amplifier module max4466 adjustable gain for arduino B Dz.For the amplification, we use the Maxim MAX4466, an op-amp specifically designed for this delicate task! Using it is simple: connect GND to ground, VCC to 2.4-5VDC. If you're connecting to an audio amplifier that has differential inputs or includes decoupling capacitors, the 100uF cap is not required.