Laser Microphone

Random Thoughts

• notch filter to block 60hz hum
• bandpass filters to block out all but voice range.
  • Possibly adjustable in case someone's voice is deeper/higher
  • The voiced speech of a typical adult male will have a fundamental frequency from 85 to 180 Hz, and that of a typical adult female from 165 to 255 Hz

Notch Filter

• http://www.members.shaw.ca/roma/nine.html
  • Has schematics specifically for 60hz hum
  • Might also be an amplifier

Audio Amplifier

• http://www.techlib.com/electronics/audioamps.html#LM386
  • Has several different schematics for amplifiers.