Outdoor electronic soundproofing

[AnnieH]

Excuse me. I am an accountant. No physics at all. But, is it possible to do outdoor soundproofing? I envisioned a setup of portable poles that could in effect soundproof an area with electonic or magnetic frequencies by blocking or effecting the sound waves coming from that area. Kind of like a cell phone or radio tower only small and portable to move with a truck or buy at Home Depot. They could be used in a small or large area, larger requiring more portable poles or taller poles. Cell phone signals can be blocked, why not sound waves? It would be a great invention for construction zones, highways, racetracks, or my teenage son's garage band. It could also make an outdoor area private like a private meeting room or a wedding. Does the military already have this technology? Is this even possible or have I been watching too much Star Trek? Seems like it could make a million $. Where are the aliens when you need them?

 

[mgb_phys]

Cell phone signals are elctromagnetic, they are blocked by a conducting (metal) screen.
Sound is a vibration of the air, the only way to stop it is to reflect or absorb the vibration - this requires something solid and heavy in the way.

There are techniques to reduce noise by broadcasting other sounds 'out of phase' with the original sound - which reduces the volume in a small area. It works well for enclose spaces and predictable low frequency noise - it's used in high end sports cars and turboprop aircraft.

 

[maverick_starstrider]

As was previously mentioned, EM (electromagnetic) waves and sound waves (which are pressure waves) are ENTIRELY different things and although the aformentioned noise cancelling technology most certainly exists it is extraordinarily expensive and complicated. Unfortunatly the poor man's answer is no. You can't really do outdoor soundproofing without computer driven noise cancellation tech (although I feel like analog noise cancellation may exist but that's still not at all helpful). Furthermore, if you were to place posts around your outdoor property it would actually DECREASE sound proofing since they would serve to reflect the sound back inwards. However, let me just say, incase people try to correct me, that an advanced knowledge of physics and acoustic engineering could almost certainly concoct a device to block noise outdoors. However, it would neither be simply nor cheap

 

[maverick_starstrider]

P.S. as you mentioned light waves can be blocked by "spamming" all frequencies near the broadcast frequency (radio, IR, UV, X-Rays, etc are all light). And similarily sound waves could be blocked by other sounds waves. However, the simplest way to do this (as it is done in radio jamming) would be like if you took your TV and turned it on to a channel you didn't get (i.e. where you get nothing but static) and turned it up so loud you can't hear what other people are saying. Which would not exactly be useful in REDUCING neighbours' annoyance outdoors. More advanced approaches to noise cancellation would require a complete control of the sound producing environment (like in a pair of headphones but not like the out of doors) and computer software/technology.

 

[AnnieH]

Thanks so much for all the information. It is very interesting.