I took some video clips of my friends as we were waiting outside of a resturant for some other friends. right near us was a mesquite tree with a very noisy cicada http://en.wikipedia.org/wiki/Cicada. sure enough, when I went to watch the video on my laptop, the cheap piezo mic on the camera sure picked up that noisy bug. I got to thinking about the World Cup last year and how they used notch filtering/adaptive filtering techniques on the audio to deal with all those vuvuzelas. Can this be done with Audacity? the cicada noise is of course going to be a much less exact pitch than the vuvuselas (which were mostly at 235 Hz), but it’s noise definitely occupies has a certain high-frequency range. Any advice on how I might accomplish this, while trying to preserve at least some of the sound of my friends’ talking? I know how to convert the video file to a WAV file already.