Must be a big chicken, per<p><a href="http:&#x2F;&#x2F;www.wavelengthcalculator.com&#x2F;" rel="nofollow">http:&#x2F;&#x2F;www.wavelengthcalculator.com&#x2F;</a><p>the wavelength in water (brain matter) of a 7 Hz tone is somewhat over 200 meters.  So probably not the skull cavity unless its some kind of chicken themed Godzilla movie.<p>The problem is likely not the skull but the neck and tendons and stuff oscillating like a bridge.