parbly so.
Just came to mind how the air is a 'strange' medium. Perhaps, one could get both 'matching' AND resonance by using a 4 ft by 8 ft panel, or large set of panels, of metal that has a solenoid mounted on it, or a motor with a counter weight on it. All these frequencies are low enough to be mechanically obtainable. AND the sheet of material would be like a large diaphragm. Everyone knows the 'shaking' sheet metal panel used in the days of radio to duplicate storm rumblings.
oops forgot. at low frequencies diaphragms are not so good. The required area gets a bit out of hand. Could do a 'linear' motor along the inside of a tube to create a compression wave. Not sure sound has the most effect. All in all, I think an electric display [flickering lights that try to sync the alpha(?) wave] and low level random noise that the brain tries to make sense of would have more impact at inducing fear response. Or, throw someone into epileptic seizures. Maybe a bit too severe?
Just remembered, not just sound but peripheral vision motion can really induce a fear response. Has something to do with the brain trying to sort out what it can't see directly, only 'sees' motion out of the corners of the eye. The trick is to make a visual 'motion' where a person is NOT looking. Requires using cameras to observe the person, something like that Sony software for interactive TV, and that free vision software to put together the system. Parbly only work on one person at a time, unless you could get an 'en masse' response. ...enough play thinking! BACK TO WORK EVERYWONE!