Unearthly Hum

[Tunnelcat]

Ever hear this one? Never heard it myself, but it sure sounds weird. It would drive me nuts if it started up here. It really vibrates the walls coming through my PC speakers. Maybe it's space alien music or something.

http://news.yahoo.com/mysterious-hum-dr ... 59328.html

[Foil]

Whatever the source, I certainly understand how a constant sound could drive one crazy. I personally have had tinnitus for over twenty years.

[Tunnelcat]

I have tinnitus as well, so I know what you're talking about, but that low, varying amplitude rumble would absolutely drive me crazy. It vibrates everything.

[Duper]

Me too. since I was 6.

[Tunnelcat]

Yeah Duper and Foil, it's mostly low key for me in my right ear, but every once in awhile, it'll ramp up in volume for no reason, almost to a screech. Then it's distracting.

Hmmm. My hubby and I were discussing this today because they played it on the news. We came up with a crazy theory. Very low frequency communication waves that can travel much farther through the earth and oceans, reaching far more areas of the planet than higher frequencies can. We're thinking very, very low frequency military communications. We're guessing that those areas where the noise is typically heard by people happen to be nodal areas that are amplifying it due to rock formations or other structures beneath the ground. Then people hear it. Just our theory mind you.

[Duper]

well if I read it right, these incidences started; as in they didn't occur/exist before a certain time.

very odd.

naw.. my tinnitus is a high pitched whistle... actually about 5 different frequencies. they're all at the high end like you used to hear as a kid in school when they tested your hearing.

It gets louder with stress. I also get ringing occasionally at seemingly random times. It fades out after a minute or two.

[Krom]

I have heard a rumbling like that, but not that loud. If you really want to hear it easily, lay your ear down on a solid connected to the ground surface (like a hand railing) near a large industrial area or an amusement park, or even a busy freeway. For instance if you listen to a hand railing in the Mall of America you will hear a sound just like that (you can actually feel the whole building rumble/shake if you just sit on a bench on the second or third floors). It is probably natural seismic waves or from some human activities and it just hits the right harmonics to be much louder in some geographic areas. Sound travels much faster and much further through the ground or the ocean than it does through the air, so it is perfectly reasonable to expect some areas might have just the right structures in the ground to concentrate and amplify the sound.

I would say test the people in the area who can't hear it and see if their hearing is as normal as the people that can hear it, or if they can't hear low frequencies as well. But I would be inclined to believe that there really is a sound there, because you can hear sound like that from listening to a railing or a signpost or a tree just about anywhere near industrial or other types of heavy activity. That sometimes people hear it miles from the nearest potential source probably just means something in the geography is particularly conductive to the sound.

[Alter-Fox]

From my knowledge of sound (as an audio engineer though, so this is not my specialty ) the lower the frequency of a sound the less information it can carry because the distance between the expansion and compression of the wave is longer. I'm not sure a sound that deep would be able to carry enough information to be useful for communication.

I would say, like Krom, that this is a completely earthly hum.

[Heretic]

It's the Morlocks civilization maintaining their ancient machines.

[Grendel]

Wind Turbine Noise ? ... ... ...

[snoopy]

From my knowledge of sound (as an audio engineer though, so this is not my specialty ) the lower the frequency of a sound the less information it can carry because the distance between the expansion and compression of the wave is longer. I'm not sure a sound that deep would be able to carry enough information to be useful for communication.

I would say, like Krom, that this is a completely earthly hum.

"Usefulness" is a relative thing, and depends upon what you need to get done. Modulation schemes are all about packing more information into lower bandwidths - it's theoretically possible to pack extremely high amounts of data into low frequency signals - though it may not be all that practical. Also consider that lower frequency sounds tend to penetrate through material better - you could conceivably create a system similar to ultrasonic system, but at lower frequencies for longer distances...

I wouldn't rule out unnatural sources...

[Foil]

.. my tinnitus is a high pitched whistle... actually about 5 different frequencies. they're all at the high end like you used to hear as a kid in school when they tested your hearing...

Mine is similar, though I'd describe it more like a 'single tone' (yes, very much like those super-high-pitch hearing-test tones) than a 'whistle'.

Mine personally never stops. I'm normally able to block it out, but when I hear a similar tone or someone mentions it (e.g. this thread), it gets really noticable/distracting/annoying.

[Duper]

Mine's a tone too. You're right, it isn't really a whistle. It explains why I used to do home work with music playing or a TV going. A bit of white, background noise helped drown it out.

I think you're onto something there Krom. It might well be where a wave nod peaks at the surface. Kinda hard to tell. varying strata will play a major role as well. Granite, clay, gas pockets.. you name it.

[Foil]

Crap. Every time I see this thread, I suddenly start noticing (and thus start being bothered by) my tinnitus.

[Tunnelcat]

Sorry about that Foil. Mine is a high pitched, single tone as well. Right now, it's in the left ear. I usually have some noise all the time and it will switch sides sometimes, but occasionally it will ramp up to a screech for no reason, then go back down, fortunately. I hate it when it does that right before I try to go to sleep, which has happened a couple of times. I never even listened to loud rock music as a kid either, which is the usual reason the docs give for getting tinnitus later on.

From my knowledge of sound (as an audio engineer though, so this is not my specialty ) the lower the frequency of a sound the less information it can carry because the distance between the expansion and compression of the wave is longer. I'm not sure a sound that deep would be able to carry enough information to be useful for communication.

I would say, like Krom, that this is a completely earthly hum.

Elephants can communicate with a very low frequency rumble, so communication is possible.

http://www.elephantvoices.org/elephant- ... ation.html

And the Navy uses it to communicate with submarines, with a system called ELF, or subradio frequency.

http://en.wikipedia.org/wiki/Extremely_low_frequency

[Krom]

With any type of signaling technology, lower frequencies travel further and easier while higher frequency signals can carry more data. It is pretty much a universal rule: As frequency rises, range falls.

They use ultra low frequency signaling for submarines because nothing else can physically reach them, but the data rates are probably pretty low.

[Tunnelcat]

But it does do the job. The question is, can it be audibly heard, or felt, if traveling through the ground?

[roid]

sounds to me like underground heavy-vehicle (ie: trucks) road traffic.
lots of tunnel-work around my city, i notice this sound when waiting at the lights while on a small bridge near the tunnel entrance/exits, it shakes the whole car (it shakes the whole bridge, they must have had to suspend it on rubber grommets or somesuch just to preserve it, it's like a constant earthquake).

pretty cool and facinating story OP, kinda wanna know more, i mean assuming it's not something benign like traffic vibrations.

[Tunnelcat]

Try going over to Bondi in Sydney and see if you can hear it roid. But since you're younger, you may have some trouble. It seems that people between the ages of 55 and 70 can hear it best.

http://www.nbcnews.com/science/mysterio ... 6C10760872

[roid]

Since it doesn't seem to be a constant thing - i'd probably have to live there to get a chance of hearing it. but i'll keep it in mind tho

maybe you'll hear it on TV? https://www.youtube.com/user/BondiRescue/videos

[Tunnelcat]

Couldn't hear it in the videos, but I think it's one of those sounds that creeps up on you if it's really quiet. Kind of like the noise of someone bouncing a basketball in the driveway next door. A low thumping you don't hear it until all other noises are gone, like when you're trying to go to sleep , THEN it bugs you.

[flip]

Eh, don't worry. It's just the sound of HAARP twisting and bending the atmosphere