Rail switch yard? The one in town here is oddly quite some days and very loud others. I know good and well they operate all the time.

Well, somebody has to, so it might as well be me...

Your neighbor's talented pet?

Honestly every once in awhile I too will here a very low rumble sound that will go for about 3-5 seconds stop for about 3-5 and start again. It will go like this for about 4 or 5 times then stop. Everyone else I have asked has not heard it. I also hear very high pitch frequency sounds every so often too. We tested this with a friend and she downloaded an app on her phone that played high frequency sounds that normally you can not hear. Whenever she played it on her phone, I could hear it. I would also tell her when she stopped playing it. God Bless

Brontide.

quote:

Originally posted by smschulz:

quote:

It could be some form of tinnitus / sinus or any number of other correctable maladies.

I wish it was correctable.

Same here. As soon as I read the word tinnitus the ringing got louder.

Maybe seismic testing, but I would think the frequency would be pretty rapid.

I believe the Ruffed Grouse is the source of your sound as someone else has previously suggested. Generally the grouse will be drumming mostly in the spring, but around here they can be heard on occasion, almost year round.

I once heard it equated to a farmer trying to start an old crank start tractor, and that is pretty close to what my grandfather's Allis Chalmers sounded like when it didn't fire off on the first few tries.

quote:

Originally posted by smschulz:

quote:

It could be some form of tinnitus / sinus or any number of other correctable maladies.

I wish it was correctable.

ME TOO!

Aliens. Most definitively Aliens.

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Originally posted by Nismo:
Over here, its the garbage trucks picking up the big metal dumpsters from the nearby shopping areas very early in the morning.

+1

quote:

Originally posted by OKCGene:
Train rolling by???

I'm with the train responses. We live about a mile from two different lines that join up about 1.25 miles away. Sometimes, there will be a train idling on one of the tracks (usually the one behind the hill between our house and the track), and it can sit there for quite some time. The idle sounds like a very low frequency "thrum". It almost seems like it comes and goes, but that's just the wind shifting. When the wind is right, I can also pick up the same thrum from a diesel that is approaching but still a long ways off, but that noise reveals itself as the engine gets closer and the engineer sounds the "engine in front approaching a grade crossing" whistle, which is two longs, a short, and a long. And it also seems to occur most often in the wee hours of the morning; sometimes during the day.
 
I used to hear the same sound when I lived in Gaithersburg MD, about 3 miles from the line. Coal trains required 3 or 4 engine "pushers" in the rear to make it up the grade to Gaithersburg, from where it was downhill all the way to DC. The rear engines would cut away at Gaithersburg, and sometimes sit there idling for some time before heading back.