Code

code taken from: http://forum.sparkfun.com/viewtopic.php?t=11430&highlight=sound
modified with Anders's help


int audioIn = 0;
int val = 0;
int ledPin1 = 2;

void setup() {
pinMode(ledPin1, OUTPUT);
Serial.begin(9600);
}

void loop() {
val = analogRead(audioIn);
Serial.println(val);
if (val <=600){
digitalWrite(ledPin1, HIGH);
}
else{

digitalWrite(ledPin1, LOW);

}
}