Ever Heard An Infrasound?
If you've ever experienced a bone chilling, hair-standing-on-end kind of feeling, then the answer is likely yes. You just don't know you've heard it.
According to Wikipedia "Infrasound, sometimes referred to as low-frequency sound, is sound that is lower in frequency than 20 Hz (Hertz) or cycles per second, the "normal" limit of human hearing. Hearing becomes gradually less sensitive as frequency decreases, so for humans to perceive infrasound, the sound pressure must be sufficiently high. The ear is the primary organ for sensing infrasound, but at higher intensities it is possible to feel infrasound vibrations in various parts of the body."
|"A unique double bass reflex loudspeaker enclosure design intended to efficiently produce infrasonic frequencies ranging from 5 to 25 Hertz which traditional subwoofer designs are not readily capable of." source Wikipedia|
Technology lecturer Vic Tandy accidently stumbled upon this phenomenon in the early 1980's, so it's not exactly new. It's been suggested that as infrasound isn't perceived consciously, that it might make people feel that odd or supernatural events are taking place.
What with Halloween being last week and all, infrasound was in the news again. Listen to what the CBC's science columnist Torah Kachur has to say about this? Simply click this link.
It would certainly be interesting to test for signs of infrasound at various local ghostly hotspots.