as sibling comment says, low frequencies are problematic. See what they put around highways, usually a 2cm thick glass and/or stone wall. Maybe put a good fence as far as possible from house?
But then there are even lower frequencies. They go through everything - they are shaking it.. thunder/rumble. A huge mass works, but i don't know if it's only way.
For example, find a hill/ridge that has the city on one side, and nothing/wilderness on other side, go on top of it. You will hear whole city - mostly low freqs. Go a bit further in the "nothingness" direction. Then a bit more. And listen.. the feeling is like your ears are being unplugged - it's that sound disappears - and you are so get used to it..
is noise from commercial aircraft low frequency? I live in DFW about 20min from a major airport and I remember going outside after 9/11 when all air traffic was grounded. It was eerily quiet even though I was still in the middle of a large metropolitan area.
Well it includes those low frequencies. I'm sure if you've flown you've experienced the strange ear-plugging feeling of flight. The fuselage is highly sound damped from the engines but you still get the low frequencies. Also could be that pretty much everyone tried to not go outside during 9/11, probably a lot more than just planes stopped
the air being pushed out/around from aircraft engines probably.
most running engines produce some low freqs, and also slow-rotational things.. like cars' wheels thumping on streets and roughnesses there.. esp. thousands of those. And then combinations of almost same freqs produce very low differentials - something on 50hz and another on 53hz will yield some 3hz. Which cannot be heard, it's to be felt.
Another similar silence happens if one is in a street/ suburb/ block-of-flats full of airconditioners-on-walls when the power goes off.
But then there are even lower frequencies. They go through everything - they are shaking it.. thunder/rumble. A huge mass works, but i don't know if it's only way.
For example, find a hill/ridge that has the city on one side, and nothing/wilderness on other side, go on top of it. You will hear whole city - mostly low freqs. Go a bit further in the "nothingness" direction. Then a bit more. And listen.. the feeling is like your ears are being unplugged - it's that sound disappears - and you are so get used to it..