10 Pcs\. Electret Microphone Amplifier Adjustable Max4466 Module Microphone 10 Pieces Electret Microphone Amplifier Adjustable MAX4466 Module Microphone Preamplifier Blue Breakout Board Compatible with Arduino Application: the MAX4466 microphone breakout is suitable for voice converters, audio recording and sampling, and audio response projects using FFT; On the back, there is a small trimmer pot to adjust the gain; You can set the gain from 25x to 125x Parameters: power supply voltage: +2.4V to +5.5V (can be compatible with STM, Raspberry Pi and other development board motherboards); Power supply rejection ratio: 112dB; Common mode rejection ratio: 126dB; AVOL: 125dB (RL = 100 thousands of ohm meter) rail-to-rail output; Quiescent power supply current: less than 24 microamp; Gain bandwidth: 600kHz 20-20KHz electret microphone soldered on: comes with a 20-20KHz electret microphone soldered on the board for audio-reactive projects; It is recommended to use the FFT driver library, which can take audio input and 'translate' it into frequencies Easy to use: connect GND to ground, VCC to 2.4-5VDC; For the good performance, use the 'quietest' supply available (this would be the 3.3V supply) Power supply noise rejection function: the amplifier has good power supply noise rejection