Add an ear to your project with this well-designed electret microphone amplifier. This fully assembled and tested board comes with a 20-20kHz electret microphone soldered on. For amplification, we use the Maxim MAX4466 op-amp, specifically designed for this task. The amplifier has excellent power supply noise rejection, delivering clear audio with minimal noise or scratchiness compared to other microphone amplifier modules. This breakout board is ideal for applications such as voice changers, audio recording, sampling, and audio-reactive projects using FFT. A small trimmer potentiometer on the back allows adjustment of the gain from 25x to 125x. Output levels can range from approximately 200mVpp (for normal speaking volume at 6 inches) up to about 1Vpp, making it suitable for microcontroller ADC readings. The output is rail-to-rail, capable of reaching up to 5Vpp when needed. To use: - Connect GND to ground and VCC to 2.4–5VDC. - For best performance, use a stable power supply, such as the 3.3V output on an Arduino. - The audio waveform is output through the OUT pin. - The output has a DC bias of VCC/2, so in quiet conditions, the voltage remains steady at VCC/2 (DC coupled). - If AC coupling is required, place a 100μF capacitor between the output pin and the input of your device. - The capacitor is not needed when connecting to equipment with differential inputs or built-in decoupling. The output pin is not intended to drive speakers or high-impedance loads. It can only drive very small in-ear headphones. For speaker output, an external audio amplifier (such as a 3.7W stereo amplifier) is required. When connecting to a microcontroller pin, no additional amplifier or decoupling is necessary.