Most of the human flesh is resonating at 7hz (real, no gimmick). There's been some ideas like, that 75db's of 7hz could be lethal. It's also said to be nauseating. Put the frequency has to come into human in a certain way, in order it to work, I guess.
Anyway, we know for sure that infrasound can make humans feel a bit scared and anxious. It has been used in some movie soundtracks.
Here's my favourite urban legen on the subject: subwoofer manufacturers have agreed not to make subwoofers play dangerously low frequencies.