A new "Sky Sound" video

Just got home from work a little while ago.....around 11:15 last night, we got a flurry of calls reporting "explosions".....officers were sent out, and found nothing! I have no idea what they were hearing, but a few people sounded really scared. I didn't hear anything however......anyone in central Louisiana hear this last night?

reply to post by StealthyKat


I keep going back and forth between fracking and arcing. I mentioned last night that the biggest difference between the fracking sound and the roaring sound is the spread of the frequencies (the fracking is grouped within a certain frequency range, while the roaring is spread out and only peaks at specific frequencies). Weeelllll, I had an idea this morning. If the sound from the fracking site is being reflected off the cloud cover, then it might be getting amplified at those specific frequencies by the Earth's Schumann resonances. It might be a superposition of the two. That would lead to the spread of the fracking sound being amplified at the specific frequencies we're seeing.

When I get the chance (probably tonight), I've got an experiment I want to try. I have an idea....

Can anyone add to this thread please- trying to track these things in one place and build a bigger picture

Cheers

reply to post by CLPrime


I posted something like that yesterday.....I was reading how someone thought it seemed to happen more on cloudy days (although I have recorded it on clear sunny days)....but....the thought came to me that maybe the clouds kind of "trap" the sound and kind of bounces it around ( funny description, but you get the idea). Is that possible? Maybe that's why it sometimes sounds like it is coming from "everywhere" Looking forward to your experiment...you're the best CL!

reply to post by facchino


Sure I will...I was just asking Gazrok today if we could open a category for this topic....like Japan has......there are just getting to be so many threads on this coming out daily and the info is getting scattered and repetitive...

Originally posted by StealthyKat
reply to post by CLPrime

 

I was reading how someone thought it seemed to happen more on cloudy days (although I have recorded it on clear sunny days)

Sometimes, the right conditions may exist without there being visible cloud cover. Maybe it's just some atmospheric condition that usually causes clouds, not necessarily the clouds themselves.

....but....the thought came to me that maybe the clouds kind of "trap" the sound and kind of bounces it around ( funny description, but you get the idea). Is that possible? Maybe that's why it sometimes sounds like it is coming from "everywhere"

That's what I was thinking. Though, as I said above, it might not be the clouds, themselves; rather, it might be some atmospheric condition that typically causes clouds to form. Maybe some sort of temperature differential, or a change in humidity/density. Or all three, since they do tend to come all in a bunch like that (we like to call it "weather").

reply to post by CLPrime


Yep....it very well could be something to consider! It makes sense to me! What will your experiment be? Something to do with that? You have me curious!

Very interesting theory,CLPrime.

Take a look at this,sound propagation with different atmospheric conditions.

Lower frequencies will tend to bounce off as higher frequencies are absorbed.

www.sfu.ca...

Under conditions of a temperature inversion (temperature increasing with increasing height), the sound waves will be refracted downwards, and therefore may be heard over larger distances. This frequently occurs in winter and at sundown. For instance, the Nine O'Clock Gun in Vancouver has been heard up to 45 miles away under the proper atmospheric conditions.

reply to post by kdog1982


I'm so glad to have all of you who have posted on my thread! You guys are great....and so smart!

reply to post by StealthyKat


My experiment is really super extreme extra top secret (I guess that means it's even too sensitive for this site).
I make people wait on the edge of their seats whenever I can. This is one of those times

If we can establish that this is the cause, this roaring sound might have to be christened the Fracking Syndrome.

reply to post by kdog1982


I guess that would make this a prime (ha...that's my name) suspect.
I'm kinda liking this theory.

reply to post by CLPrime


I must add also,CLPrime,you have an excellent reputation on here and highly respected by me and others.
So,keep up the good work!

reply to post by CLPrime


God CL....you are soooooooooo mysterious!!!! I love it though....I'm sure it will be fracking great hehe....Seriously though, I can't wait!

I have a feeling the neighbors will be calling the police on CL and we won't be hearing from him for awhile.

Does your experiment have to do with really loud speakers and explosives???

reply to post by kdog1982


Maaaayyybe. Though, even if the neighbours do call the cops on me, it'll be at least 45 minutes before they get here, so I'm not really worried. Not that they'd care, anyway. We have the opposite of abusive cops... ours specialize in apathy.

I'm waiting for everyone to go to bed before I do anything. It'll probably be a couple hours yet. But, I will say this...there are no loud speakers involved. Explosives...possibly.

reply to post by kdog1982


He's a sly one alright....

reply to post by CLPrime


You're scaring me CL....as Hannibal Lecter said to Clarice...."I think it would be quite something to know you in real life" Gotta leave for work......I can't wait for the results!
See yall in the morning.

reply to post by StealthyKat


Funny that you should bring that up. There is actually one of Hannibal's traits from Silence of the Lambs that I tend to mimic. You can guess what that is.

And, I'm doing the experiment now. If you never hear from me again, you'll know what happened.

reply to post by CLPrime


Made it through the experiment with no cops called. Didn't even wake my parents up, I don't think. And, unfortunately, there were no explosives.

So...the results:

It comes in quite handy that this is winter, because our furnace through the registers just happens to sound very similar to the sound people have been hearing. In fact, based on recordings of both, it's pretty darn close.

I took a spectrograph of the furnace near a register, as a control:



In case you don't know how to interpret that, the real-time frequency spectrum is along the bottom (though that's not what we're concerned with). The area above, with the blue stuff, is the important part. This is a spectral analysis over time, with the time axis going down the screen (real-time at the bottom, and about 1 minute ago at the top). The frequency spectrum runs across the screen, perpendicular to time (as the Hz labels show), and the colours denote amplitude. A brighter blue is a higher amplitude (a louder sound).

So, that's the sound itself, recording with the laptop mic next to the register to get the pure sound with no effect of distance. It's a predominantly 120-400 Hz sound, diminishing smoothly beyond that with increasing frequency. This is very similar to the fracking sound, which was also grouped in a specific range and fell off gradually from there.

Also, the red line running up the left side marks the 8 Hz frequency (I marked it just in case anything was "heard" at the 7ish Hz frequency, so I could see it).

Now, part 1 of the experiment:



This is the spectral analysis of the furnace sound as heard from about 6 feet away.
Still paying attention to just the top of the image, with the blue lines, the top half (above the obvious horizontal blue line in the middle) shows how the sound is now focused at two frequencies - 120 and 240 Hz.
The bottom half is to establish the effect of confining this sound. I took two blankets and used them to cover the distance from the register to the laptop. As you can see, the effect was that the 120 Hz frequency stayed the same, while the 240 Hz frequency was significantly reduced, as was the more faint region in between (albeit to a lesser degree).
This is exactly what I expected to see. This indicates that the confinement caused higher frequency and lower amplitude sound to be absorbed and/or dispersed, leaving a localized low-end frequency. This would explain why the spread of the fracking sound became localized to a couple low frequencies.

And, finally, part 2:



This was to test the effect of temperature, and it's a normalized spectrum to make any changes more obvious.
Again, the colourful part is divided by a horizontal line. The top half is the control - a recording with me holding the laptop and standing next to the register.
For the bottom half, I opened our very handy patio door. Just for the record, it's -6°C (21°F) outside and 28°C (82°F) inside. I believe that qualifies as a significant temperature differential.
The effect would have been too subtle to notice without the normalization, but it's pretty clear here. The sound, below 400 Hz, is amplified.
Again, I'm not surprised. kdog's link supports this.

So, we have two things happening:
- we have a localization of low frequency sound in confinement, accounting for the frequency spread of the fracking sound becoming localized frequency peaks after having travelled some distance within some sort of confinement;
- and we have an amplification of this sound by a significant temperature differential (for instance, a temperature inversion), giving us a suspect for what is confining the sound and allowing it to travel such distances.

Put these together and you get an otherwise uninteresting fracking sound being turned into an ethereal roar over some distance, under the right conditions.

reply to post by CLPrime


**waves hand frantically in the air" Ooooh Ooooh.....I know what it is! (what you are imitating) Your stance in your avatar is how Hannibal stands in his cell?????