bmuss, the first physics resonance definition is more relevant for this case.
"Physics: The increase in amplitude of oscillation of an electric or mechanical system exposed to a periodic force whose frequency is equal or very close to the natural undamped frequency of the system."
So when resonance happens with most aftermarket exhausts it usually causes mechanical vibrations, as well (in addition to the air-borne waves i.e. amplified sound). IMO, that's what really makes them undesirable to people who dislike them. Designing an acoustical system is not unlike designing an electic RLC circuit, and is far from trivial. Hence, the top $ demanded by Porsche for their smooth sounding PSE. Those engineers have mortgages to pay.
Z.
Threaded Mode
