There can be an overall resonant frequency.
The catch is that it will vary from person to person, and also from condition to condition- did you eat recently? did you take a major shit? is your bladder full?

So there isn't a magic frequency that will work all the time, or even one that will work most of the time.

Too bad, as that could have some really interesting applications.
( The Resident Loon Not a demographic. Do not measure., Tue 29 May 2012, 22:52, Reply)