arduino--Sound sensor

Arduino program: (First autocalibrates microphone, you must be quiet, then sends only the positive values of the sound wave) 

Piezoelectric Sound Meter

http://www.nerdkits.com/videos/sound_meter/

參考資料:

Arduino listens to electret microphone

http://www.dtic.upf.edu/~jlozano/interfaces/microphone.html

Hobby Robotics...利用arduino製作光與聲音偵測器

http://www.glacialwanderer.com/hobbyrobotics/?p=11

The World Famous Index of Arduino & Freeduino Knowledge

http://www.freeduino.org/

processing
http://disp.cc/b/56-3h8