for a step-by-step overview.
Entertainment Sound Isolation
Typical residential construction is adequate
at keeping low-volume, high frequency sounds (such as
speech) from traveling through the rest of the household.
People talking in one room can often be heard in an adjoining
room, and low muffled sounds can sometimes be heard between
floors. When "frame" construction with drywall
became popular in the 1950's, large sound systems and
home theaters were only a futuristic dream.
Today we find ourselves with an ever-increasing
problem: Structure-Borne Sound Transmission of low frequencies.
That "Thump! Thump! Thump!" of a subwoofer going
through the structure of the house and annoying everyone
who's not in the listening room.
- -Why Isolate the Room?
Being an acoustical design and engineering
firm, we began receiving many calls for help from disenchanted
homeowners. These people had recently invested in a dedicated
home theater system, only to find they had inherited an
unforeseen problem: excessive bass that could be heard
throughout the house.
What was expected to bring an added degree
of enjoyment to the family, was now a source of discontent.
Those watching the movie wanted BIG sound and with earth
shaking bass. However, the rest of the family in other
parts of the house couldn't stand the constant thumping
and vibrations they were being forced to deal with. One
party was constantly yelling "turn that thing down!".
While the other party tries to inch the volume up in an
effort to get that Large Cinema feel. Nobody was happy
in the end.
We would hear tales of people trying everything,
from pillows under speakers, egg cartons on the walls,
to ropes suspending equipment off the floor. Nothing seemed
People would call us at ASC asking about
our bass traps. "Would they work? They do absorb
bass...right?", many would ask. Unfortunately, bass
traps are not the answer. Yes, they do work great at absorbing
excess bass reverberation and controlling room modes,
but do little in the effort to control structure-borne
sound which was the problem they now were facing.
So, what could be done? Unfortunately for
them, very little-unless they were willing to undertake
a major remodeling project of their home theater room.
This would require a rebuild of all the walls and ceilings,
an option not too popular with most.
- -The Root of the Problem-
The real problem is, the room was not designed
or constructed to withstand such severe sonic impacts.
When a subwoofer produces powerful low-frequency
acoustic energy, that wave front travels through the room
and then collides with the wall & ceiling surfaces.
Upon collision, much of that kinetic energy of the wavefront
is converted into mechanical (vibrational) energy, which
sets the thin, flexible wall surface into vibration. This
vibration is easily conducted through solid surfaces it
is in contact with, such as the studs, joists and flooring.
The vibration travels up and through the framing of the
house, vibrating the walls, floors and ceilings as it
passes them. What you get is a quaking house full of noise.
This is what is known as Structure-borne Sound Transmission.
The fact of the matter is, conventional
wall & ceiling construction methods easily conduct
low-frequency sound, and are poor at blocking them out.
- -The Solution-
There are three ways to keeps sound from
traveling through a structure:
- Block the sound by increasing the mass
(thickness & density) of the walls.
- Minimize the transmission paths for vibrations
and sound to travel through.
- Dampen the vibrational energy.
Only Acoustic Sciences' proprietary ASC
Iso-Wall System incorporates all three of these methods.
- Our system uses a double layer of gypsum
to achieve twice the mass of an ordinary wall. At the
same time, we minimize resonant coupling by using materials
of differing density.
- Path sources are reduced by "floating"
the walls & ceiling off the studs, while also giving
the room a tight acoustic seal at all potential openings.
- Vibrations are quickly damped and the
energy absorbed by utilizing our special WallDamp material.
Configured in a constrained layer method, three separate
interface points are addressed to insure maximum benefit-at
the stud, on the channel surface, and between the layers
You get walls & ceilings that achieve perceptible
sound volume levels SIX times * greater than
standard interior walls.
With a calculated STC range of 50-60dB (Sound
Transmission Class), it makes our wall system one of the
highest available using standard single-stud construction.
But, what truly puts the ASC Iso-Wall System
in a class by itself is the remarkable ability to control
and dampen low-frequencies. That boom! boom! boom! produced
by sub-woofers. By incorporating our proprietary energy
absorbing Walldamp material, vibrations from sub-sonic
concussive events are quickly dissipated and the energy
that can travel through the structure is minimized.
Other sound isolation methods simply do
not measure up.
* As measured
in sones, a unit of subjective loudness as perceived by
- -How to Order-
The Iso-Wall System is sold as a complete
kit, ready to be installed by your local contractor or
as a do-it-yourself project. All you need to provide is
the drywall and screws. Simply provide us with the dimensions
of your room, and we will send a complete kit with all
necessary materials and step-by-step installation instructions
to complete your room. Of course, you may call one of
our technical representatives at any time with questions
or for assistance. Pricing for the kit materials is typically
less than $5 per sq/ft. of wall and ceiling surfaces.
Speak to your local ASC Distributor, or
call Acoustic Sciences directly at (800) 272-8823.
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