Sensor for sound detection, the module has two outputs:
AO, analog output, real-time output voltage signal of the microphone
DO, when the sound intensity reaches a certain threshold, the output high and low signal
The threshold-sensitivity can be adjusted via potentiometer on the sensor.
[For more information](https://www.adrirobot.it/sensori/37_in_1/KY-037_KY-038-Microphone-sound-sensor-module.ht...