A Subwoofer Too Far (History Lesson)

[DrDyna]

Just for fun:

 

[AndrewT]

Here are a few links to sites relating the human body's dislike for frequencies around 7Hz.
Deadly Frequencies
A Short History of Sound Weapons Pt2: Infrasound | stalker
ePanorama.net • View topic - Dangerous Frequencies below 20Hz
Acoustic Trauma : Bioeffects of Sound
http://www.ktu.lt/ultra/journal/pdf_64_3/vol.64-no.3-2009_06-guzas.pdf

 

[Tom Danley]

Hi Guys
There is and isn’t a brown note. If one is speaking of airborne sound, then at least in the range above 3Hz and pressure of 132dB (about 2 lb/sq foot peak pressure), there is no such effect.
In a book I have on Infra sound and vibration, it went into some of the testing in the “right stuff” era. To be CLEAR there are major problems with body resonances BUT these are mechanical vibration (like applied to your chair). Acoustically, our ears have a vent (Eustachian tube) which equalizes the back pressure with decreasing frequency, this way changes in weather don’t deafen us. We would see this same effect if we used a vented box speaker as a microphone.
It was the research in hat book that made me feel a bit safe when I tried the sonic boom the first time while standing between it and the old house. The sound of a sonic boom from a really large thing like the space plane was going to be had a 3Hz fundamental frequency in the shape of a capitol N or N wave.
This was a sharp rise to the positive value and then a more or less straight decay to a negative value, then a recovery to zero. It sounded like KAAHBoom. We had a push button that triggered the signal and I stood between the house and hit the pickle a dozen or more times in quick secession. The only thing I felt was sort of a sense of relief when I stopped.

http://cdn.avsforum.com/4/4a/4a79b243_vbattach180971.jpeg

Look at his pants. No brown note in this one either;

https://www.facebook.com/video/video.php?v=3255866089604

Best,
Tom

 

[col]

Didn't the Mythbusters deal with the brown note? Can't believe it keeps getting rolled out.

Also, Kate Bush did quite a good track about a scientist commisioned to make a sound weapon.

Experiment IV

We were working secretly for the military
Our experiment in sound was nearly ready to begin
We only know in theory what we are doing
Music made for pleasure, music made to thrill
It was music we were making here until
They told us all they wanted
Was a sound that could kill someone from a distance
So we go ahead and the meters are over in the red
It's a mistake in the making

From the painful cries of mothers to a terrifying scream
We recorded it and put it into our machine

They told us all they wanted
Was a sound that could kill someone from a distance
So we go ahead and the meters are over in the red
It's a mistake in the making

It could feel like falling in love
It could feel so bad
It could feel so good
It could sing you to sleep
But that dream is your enemy!!

We won't be there to be blamed
We won't be there to snitch
I just pray that someone there can hit the switch

They told us all they wanted
Was a sound that could kill someone from a distance
So we go ahead and the meters are over in the red
It's a mistake in the making

And the public are warned to stay off

Writer/s: BUSH, KATE
EMI Music Publishing
Lyrics Licensed and Provided By LyricFind

Watch the great vid!

http://www.youtube.com/watch?feature=player_embedded&v=NTUcoR8_pyE

col.