If You Could Meet 5 People From Graal....

[Draenin]

Originally Posted by Raziel

What causes the low hum? That's crazy...

Well, I actually read a report on it (The actual PDF of the original document that was scanned.) and a lot of it has been traced back to some of the factories that are around the area. Some sound engineers took acoustic readings in the houses of people who complained about it, and found that it would sometimes be present in some parts of the house, and not in others, or in specific spots.

The noise is a low-frequency hum at less than 20 Hz. (Lower than the ordinary scope of human hearing, which is 20 Hz to 20,000 KHz, I believe.) The areas emitting the noise have been silenced, but it's still present.

I actually found a program some months ago used to generate hums at the frequency you specify, and could slightly hear noises above and below the ordinary range of hearing. However, after turning the sound way up and listening for a while, I started to feel sort of sick to my stomach as well, and got a headache. Same goes for when the pitch of the hum was above or at 20,000 KHz. If you want an idea of what a high-pitched hum like that sounds like, I believe ads are still being played for 'the messengers' or whatever that mentions them.