We were in northern Indiana and Chicago over the last weekend, camping and enjoying the Bluesfest in Grant Park.
At the campground, we were not far enough from the highway to avoid the noise...and there was a busy railway next door. Even through this din, it was clear The Hum was not nearly as bad as at home.
At the festival, the swag tent was selling Etymotic ER-20xs earplugs for $20, tax included. I bought two, intending my partner to use the others if she needed them. We'd brought our Mack's earplugs along, so I tried a little a-b testing between the two...just to see how effective the Etymotics worked cutting down the volume without completely shutting down the mid- and high-frequencies.
The ones they were selling only had the 'normal' sized flanges, which didn't seem to grip before bottoming out and causing some pain...I knew from their excellent ER-4 headphones that they had other flanges or foam available for a better fit. So I had to wait to compare fully.
The accessories for the ER-4 'phones work with the ER-20s, so if anyone tries these...buy the slightly more expensive kit with the various fittings. Five bucks more and you've got three options instead of the one.
With the larger rubber flanges, the ER-20ax earplugs work wonders. They reach down into the troublesome lower frequency region quite well, which is not what I expected. Every other earplug than the Mack's silicone gobs seem to not get in the way of the deepest tones at all...but these do.
Inspecting them closely doesn't reveal what seems to cause a bit of valving of the incoming flow versus the out-going...but I suspect their filter material is directional. There is a small chamber which funnels into a small labyrinth...making the sound waves change direction and travel some distance before entering the ear canal. At the very end is that filter, then the tube extension of the rubber flanges.
All I can say is they attenuate the troublesome issues, and are not tough to sleep with. While the overall sound is not lowered by the same margin as the silicone from Mack's, enough midrange and higher frequencies pass through to allow decent critical listening. But the sound is reduced to a level where normal breathing begins to intrude on outside perception.
So, while at $25 they are more expensive than the Mack's...the fully reusable Etymotic earplugs do a decent job making the Hum manageable. They compliment my fifteen-year-old investment of their excellent ER-4 headphones perfectly, I'm almost embarrassed that it took so long to 'discover' their earplugs.
https://www.etymotic.com/consumer/he...er20xs-uf.html
Cheers,
John
Last edited by Gannon; June-18-16 at 12:10 PM.
It's not the same but this paragraph reminded me of the simple genius of the Tesla Valve.... Inspecting them closely doesn't reveal what seems to cause a bit of valving of the incoming flow versus the out-going...but I suspect their filter material is directional. There is a small chamber which funnels into a small labyrinth...making the sound waves change direction and travel some distance before entering the ear canal. At the very end is that filter, then the tube extension of the rubber flanges....
Last edited by Jimaz; June-18-16 at 01:17 PM.
Geez, that is great.
Along with his water pump/generator design with the closely-spaced discs, this further cements Tesla's genius well beyond the electrical and magnetic!
Now...how to make a series of these into a sound absorption panel?!
I'm guessing the internal volume would make the high-resistant opening into a decent Helmholtz resonator, cannot remember if the high-Q would make it more frequency-specific or broadband. I'm guessing it would be a black hole absorber at the wavelength that equals the diameter of the opening. Now I've got to build some and see what happens when they're made into a matrix.
You just made my brain explode. You and Tesla...
[[who's got a 3d printer that can build something 24 inches wide?!)
A podcast called "20,000 Hertz" will be doing an episode about the low-level hum soon. I'll post a link once they publish it.
Paging Gannon for that..... he's not posted in a while.
That is really sad.
The podcast about the subject came up. For those of you already familiar with it, you're probably not going to learn much. I was hoping it was going to be a little more extensive.
https://soundcloud.com/defactosound/...rnment-coverup
Here's a followup article with a lot of theories from readers:
Readers offer suggestions to help elderly Sterling Heights woman solve noise mystery
Reed’s reaction: “No. I know what tinnitus is,” she said. “This is not just a ringing in the ear because I can feel it vibrating in my chair, in my bed. … When it gets that bad, my dog is running around trying to get away from it.After reading in that article about the 30 Hertz theory, I suspect the Romeo Engine Plant."I could not believe it when I read your article. Tell Mrs. Reed she is not going crazy. Someone else hears that same noise too. But I live near 26 Mile Road and Van Dyke. Nowhere near where she lives. I’ve been dealing with this mysterious, low frequency humming or throbbing noise for almost two years now. I have not had a proper night’s sleep since then. The level is different throughout the day but the noise always persists.
Where I used to live, I had no heavy industry within a ten mile radius except the Engine plant. Having worked with and around heavy machinery for thirty years, it was most notable when it felt like a huge industrial motor shuddering to a stop. [[All night !)
Since I moved to Rochester, I have not felt a thing. I hope she finds relief.
Last edited by Bigb23; December-15-16 at 03:19 PM.
Is there any escape from noise!
I have been cleaning and organizing over the past few weeks...happens every year, whether I need it or not [[!!!!).
Found a lousy print-out of an article from September of 2012. Went looking for it, and realized it only exists in the Wayback Machine.
Curious.
Went back into this thread and realized it had been linked to at the time...and I commented on it a bit.
Here is the Wayback Machine link...for anyone interested in one of the most comprehensive analysis of The Hum that I've read to date. It might not be as exciting as 20 pages here...
http://web.archive.org/web/201301270...um/hum-nux.htm
Enjoy!
A quick search on googlescholar leads to him as author of a book about HAARP.
"Secrets of Cold War Technology"...out of print but kept in some very curious libraries.
Damnit...why do I always have to stumble upon these little rabbit holes?!
One for our dearly departed Gannon. VICE News reported on the hum last week.
See Video article here:
https://news.vice.com/story/the-myst...dians-can-hear
I always hear ringing in my ears but that is from not wearing hearing protection while working in an auto plant.
As a side note, relatives that used to live in Lonyo / Dix area used to claim their house shook because of excavation from the Detroit Salt Mine. Hard not to believe industry is the cause of this noise.
Came across this today.
https://youtu.be/jhXaM_r80_c
I'm gonna toss something out here that you can explore or ignore at your whim. I noticed something a couple of weeks ago and thought of this thread.
I could distinctly hear something that I could not identify at first. This is an agricultural area with some other machinery including boats. At first, I was pretty sure it was something like that off in the distance, but I couldn't pick it out. I noticed it didn't really matter which way I turned my head though.
I'm not really sure how I came to realize it, but I'm almost certain it was the blood flowing through my system near my ear. My BP is a bit high, but not enough that they want to treat it. There is also some tinnitus. And some sinus issues that keep the left side partially blocked and running/draining. That causes the sensation that many get only when changing altitude -- the one where you feel your ears are about to 'pop'.
But on this particular day, my left sinus and ear were plugged slightly more than normal and I could tell that the pitch/drone changed just slightly with each heartbeat. I could stand completely still and hear the blood flowing and it was that same hard to identify, low frequency, muted sound people have described in this thread.
Last edited by Meddle; June-27-17 at 08:16 AM.
Makes sense. There used to be a lot of speculation about Zug Island and other industrial enterprises but what you bring up is interesting. I wonder if there is evidence of similar phenomena close to mining operations near habitations in other towns and cities. There is also the problem of fracking in Pennsylvania and Ohio or other states and provinces that might provide clues.
Thread dead for more than a year and a half. Is the hum gone now? Or are people resigned to just live with it so there's nothing more to discuss?
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