How Do the Rave Goggles Work?

The mic/amp breakout uses Maxim Integrated's Max4466 to amplify sound detected by the electret microphone. The breakout circuit outputs an analog voltage directly related to the incoming audio signal picked up by the microphone when it is powered properly. We can use this signal to our advantage by attaching it to an analog input on our microcontroller.



Changes in volume are detected by comparing the analog-to-digital converter's (ADC) result to a threshold value that we include in our program. With some test signal, we can analogRead() the varying signal level on our analog input pin. Using thresholds, we set three different volume categories and adjust the NeoPixel's color accordingly.