Electret Microphone Amplifier - MAX4466 with Adjustable Gain

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, it uses the Maxim MAX4466, an op-amp designed for this delicate task, featuring excellent power supply noise rejection for clear sound without scratchiness.

This breakout is ideal for voice changers, audio recording/sampling, and audio-reactive projects using FFT. The gain is adjustable from 25x to 125x via a small trimmer pot on the back, allowing output from about 200mVpp to up to 1Vpp, suitable for microcontroller ADCs and line-level inputs. The output is rail-to-rail, going up to 5Vpp for loud sounds.

Usage is simple: connect GND to ground, VCC to 2.4-5VDC (best performance at quietest supply like 3.3V on Arduino), and the audio waveform is output from the OUT pin. The output is DC biased at VCC/2. For AC coupled audio input, use a 100uF capacitor between output and device input. Not designed to drive speakers directly; use an amplifier for that.

Perfect for Arduino audio-reactive projects (using FFT libraries) and CircuitPython sound reactive projects. Example projects include voice changers and sound-reactive NeoPixel pendants.

• Includes 20Hz to 20kHz electret microphone
• Adjustable gain from 25x to 125x via trimmer pot
• Uses Maxim MAX4466 low-noise op-amp
• Output DC biased at half supply voltage
• Supply voltage: 2.4V to 5V DC
• Output rail-to-rail up to 5Vpp
• Ideal for connection to microcontroller ADC inputs