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Re: Noise Pollution

Subject: Re: Noise Pollution
From:
Date: Mon, 11 Feb 2002 09:00:13 EST
Joop,

I have tried all kinds of things to reduce unwanted noise. None of them work 
well. Parabolic reflectors with a foam back and a three surface PZM's help 
with isolating the sound you intend to pick up. Filtering at the mic also 
helps a little. The best thing to do is to get closer to your subject, and 
turn the gain down. That way the noise pollution is insignificant and post 
filtering works much better without affecting the signal you want. Good 
soundscape recordings require quiet backgrounds, found in the ever decreasing 
areas away from cities and highways.

Trains and planes are the worst offenders in the noise pollution problem. 
Planes observe no boundaries in the air, and trains are often found in some 
of the nicest areas. I once measured a train with a sound level meter from 
six miles away. It measured 80dB, below 100 hertz.

Quiet areas are still around, most of them in the U.S. are west of the 
Mississippi River.

Bruce

In a message dated 2/10/2002 8:01:20 AM Eastern Standard Time, 
 writes:


> I experience a continuing growing problem with noise.
> Because of growing population there is always some kind of
> unwanted noise somewhere. You can name them all, plains,
> trains, highways, farmers with machines or a loud radio on
> some populair station. Is it the right way in using all
> kinds of systems afterwards? I experience the same problems
> with overdone or degrading the wanted sound too much by
> cutting too much. With computers today all kinds of
> unbelievable filters can be used. But with severe cutting
> you degrade the wanted sound often too much. I'm wondering
> if it might work when you use a hightech filter between the
> mic and the recorder or by using a shotgun with an out of
> phase random mic for noise canceling. I suppose its not an
> easy task because you have too set the equipment to a
> certain level so your ready for recording instantly. Whats
> your opinion about this?
> 
> Joop Nijenhuis
> 
> 



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