This sound sensor module works with arduinos and many 3V-5V microcontrollers. 

AO: Analog Output - connect to any arduino analog input pin 
GND: Ground
VCC: Power supply input range: 3V-5V.
DO: Digital Output - Goes HIGH when sound is above a certain threshold. (Set by the pot)

IMPORTANT: To calibrate the set point turn the potentiometer screw many times COUNTER CLOCKWISE until LED2 turns off. The sensitivity level can be seen at the analog output.