- Space. The more space there
is, the more noise reduction there is. As an exaggeration,
if
you are 10 miles away, you
will not hear it, except under strange circumstances.
- Mass. A six foot thick concrete wall
works great!! If it is heavy, it will work well. Remember,
if it does not
weigh much it will not stop much.
- Dampening. This requires a little explanation.
Like a wine glass, when you make it ring... but you can keep
it
quiet by holding it. You have dampened the noise by retarding
the vibrations. This can be achieved in several ways.
Lead is heavy and soft; the softness makes
it also dampen the noise and lead is an excellent noise stopper.
Making
noise transfer through different layers of material with
different densities also helps dampen noise. Improperly done
it can make things worse, like string holding chimes help
them ring by isolating the vibration instead of dampening
it.
This is a very important principle to understand about soundproofing.
There are two types of noise reduction and they are almost
always confused with each other. All noise reduction and
soundproofing are not alike. Noise absorption is not noise
reduction.
Noise Reduction is achieved by stopping it, killing it, not
letting the noise get through the wall or window. Stop
the noise before it gets to you, or into the room you are
in. For this you use mass and space. You can build heavy
walls with large air spaces and you maximize dampening
as best you can.
Noise absorption is achieved by changing
the characteristic of the noise. Stop it from echoing. Stop
the reverberation.
Stop the noise reflections. All this involves handling
the noise that is within the room. It seldom involves noise
from outside the room. You have likely heard of a room
as being a “live” room or a “dead” room.
For this type of noise reduction or soundproofing you will
use carpets, upholstered furniture, acoustical ceiling
tile, soundboard or interior walls.
What works for noise absorption does not ever work for noise
reduction. Yes, you heard me correctly: soundboard is useless
at stopping noise. When put up with the sheetrock it is useless
unless it is the outside layer and it is being used for noise
absorption sound control.
Click on soundproofing to
continue.
|
