For sound detection module has two outputs:
1. AO, analog output, real-time output voltage signal of the microphone
2. DO, when the sound intensity reaches a certain threshold, the output high and low signal

Module features:
1. there is a mounting screw hole 3mm
2. the use 5v DC power supply
3. with analog output
4. there are threshold level output flip
5. high sensitive microphone and high sensitivity.
6. a power indicator light
7. the comparator output is light