Well, I just got back from a 2 week RV trip to yellowstone, and the entire way, noise was terrible. I had to pump my ATH-m50s to 75% volume on my iPod touch! I thought.. Boy, I wish I had some noise canceling headphones. Then another thought crossed my mind. When I last used noise canceling headphones (the best of the best, 375$ bose) They were excellent at cancelling noise, but the sound quality of the speakers kind of sucked in comparison to my M50's I didn't know much about noise cancellation, but I knew that microphones took ambient noise from outside, and added an inverse to that noise to nullify the wave. So my idea was to add mics to the outside of my good quality headphones, and ether make a circuit (like the headwize byRyckebusch) or possibly eliminate the circuit, and do the calculation at the SOURCE! My iPod Touch, and add it in-line to the output (my headphones) The only problem? I don't know much about the iPod touch SDK, or hardware. So, I thought this might be a good forum to look on for help. I was thinking of putting the mic inputs as pins 12 and 13? I need a better analyzation of the pinout Apple iPod, iPhone (2g, 3g), iPad Dock connector pinout and wiring @ pinouts.ru that would let me put the right and left mics in, and use the signals that come from them. Then there is the question of the iPod using that signal, and having a mix of direct de-amplification, and an algorithm like the one used in the bose headphones to still allow you to hear people talking to you. This is a fairly large project, but hopefully hardware will be minimized if I can find a way to get input directly into the iPod. Thanks!