sound proofing
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Learn how to easily install an acoustic drop ceiling and recessed lighting with these step-by-step instructions.
o hacksawo wire cutter
o laser level
o hammer
o measuring tape
o pencil
o wall angle
MATERIALS
o ceiling panels
o graph paper
o nails
STEP 1
Draw a Room Scale
Draw the exact dimensions of the room to scale on graph paper. Choose from either a 2' x 2' or a 2' x 4' pattern. The pattern size will determine the material requirements for the ceiling. For the 2' x 4' pattern, install the patterns in a standard or reverse pattern. Each pattern offers a different appearance.
Sketch various layout possibilities for the planned ceiling. It is important to space the cross tees so the border panels at the ends of the room are equal and as large as possible. With a 2' x 4' pattern, space the 4-foot cross tees 2 feet apart. For a 2' x 2' pattern, add 2-foot cross tees between the midpoints of the 4-foot cross tees.
STEP 2
Choose the Lighting Location
If the ceiling will be recessed and built-in lighting will be installed, decide where to locate the panels of light and clearly identify them on the drawing.
Determine the exact height at which the suspended ceiling will be installed. Allow a minimum of 3 to 4 inches for clearance between the old ceiling and the new ceiling. Keep in mind that additional clearance will be required if recessed lighting is being used.
STEP 3
Attach Wall Angles
After locating the exact position for the suspended ceiling, use a level to draw a line completely around the room indicating where the wall angle will be applied. Don't assume the original ceiling is level.
Fasten the wall angles securely at all points. Nail them to studs, or use screw anchors or other fasteners on brick or masonry walls. Position the wall angle so that the bottom flange rests on the level line you have drawn on the wall. Overlap the wall angle on inside corners, and miter the wall angle on outside corners. Make a temporary wooden miter box if you don't have one. Cut any needed angles with metal cutting snips or a hacksaw.
STEP 4
Install Wiring
If recessed lights are being installed, place the wiring before putting the suspension wires in place. For recessed lighting, use either 2" x 2" or 2" x 4" drop-in lighting fixtures, which are specially designed for this purpose. Fluorescent light fixtures can also be centered over the panels and a luminous lay-in panel can be used instead of a regular ceiling panel.
STEP 5
Attach Suspension Wires
Main tees should always run at right angles to the joists in the room. Locate the position of each main tee by stretching a tight line from the top edge of the wall angle on all sides of the room at each position where the main tees are to be placed.
Now, cut the suspension wires to the proper length. The wires should be 12 inches longer than the distance between the old ceiling and the new guideline string. Locate the first suspension wire for each main tee directly above the point where the first cross tee meets the main tee. Check the original sketch of the room to determine this location. Be sure the suspension wires are securely fastened. Apply them to the ceiling with screw eyes, screw hooks, nails, or by drilling. Attach a suspension wire every 4 feet along the level guideline. Stretch each wire to remove any kinks and make a 90-degree bend where the suspension wire crosses the level line.
STEP 6
Splice the Main Tees
Refer to the layout sheet to determine the distance from the wall to the first cross tee. Measure this distance along the top flange of the main tee and locate the slot just beyond this point. From this slot, measure back the same distance, subtract 1/8" and saw the main tee at that point. The 1/8" subtraction is for the thickness of the wall angle. If the wall angles are not square, position the cross tee slots accordingly. When main tees are installed in rooms less than 12 feet across, cut the main tee to the exact measurement of the room, allowing 1/8" for the thickness of the wall angle. For rooms wider than 12 feet, the main tee can be spliced. Be sure to align the splice so that the suspension wires are correctly positioned. Splice carefully, or all the main tees will be thrown off.
STEP 7
Install the Main and Cross Tees
Install the main tees so that they are all level with the wall angle already mounted. Use a long level for this. Install the cross tees by inserting the ends of the cross tees into the slots in the main tees. Use the manufacturer's instructions for fitting the cross tees into position. Determine the location of the cross tees by the pattern selected
STEP 8
Place the Ceiling Panels
Drop the ceiling panels into position by tilting them slightly, lifting them above the framework and letting them fall into place.
Soundproofing a Floor
Learn how to soundproof both carpeted and hard floors to reduce noise pollution in your home.
2007 Dorling Kindersley Limited
INTRODUCTION
Combining acoustic underlayment with acoustic mats beneath a floor reduces the effects of both airborne noise from televisions, stereos or speech and impact noise from footsteps and furniture being moved. If the problem is solely impact noise, underlayment alone may suffice. Remove the coverings to reveal the floor. If the floor is to be carpeted, leave the baseboard in place and proceed as shown below. For other floorings, remove the baseboard molding and lay out the acoustic underlayment, butting the lengths up against one another and allowing them to lap a short distance up the wall. Tape all joints, and then lay acoustic mat, ensuring that any seams do not coincide with the joins of the underlayment. Lay a floating tongue-and-groove chipboard floor over the top, and trim the edges of the underlayment. You may then install further floor coverings, such as laminated flooring.
STEP 1
Flooring Materials and Soundproofing
As soundproofing involves the building up of materials, thick floor coverings are more soundproof. For example, cushioned vinyl is more effective than regular vinyl. You can lay sheet vinyl over a soundproofed chipboard floor and attach it with double-sided adhesive tape. Similarly, high-quality burlap-backed carpets will prevent sound travel better than cheaper foam-backed carpets.
Do not add flanking strips to a carpeted floor. The fact that the carpet stretches across the tackless stripping and makes contact with the baseboard should provide protection enough against flanking noise.
STEP 2
2007 Dorling Kindersley Limited
Soundproofing Hard Floors
A combination of acoustic underlayment with acoustic mats and chipboard sheets is a very straightforward option for effective soundproofing. Here it is installed below a floating chipboard floor, over which underlayment and laminate flooring are laid.
STEP 3
2007 Dorling Kindersley Limited
Soundproofing Carpeted Floors
When soundproofing floors that are to be carpeted, first install furring strips around the room’s perimeter, then lay acoustic mats and underlayment between, and butting up against, the furring strips. Attach tackless stripping to the furring strips and lay the carpet.
STEP 4
Reducing Sound Travel
Sound is created by vibrating material. Making a room stiff and thick reduces the amount of sound that can escape. Using acoustically efficient materials to add mass to a structure increases its ability to absorb sound.
Structural elements carry sound, so creating a barrier between them prevents sounds from traveling across a room.
Use acoustic sealant, flanking tape, or flanking strips to isolate a structural element.
Seal the edges of walls and floors to prevent sound from traveling to the next room.
Soundproofing a WallWhether you want to reduce noise pollution or create a theater-like experience in a media room, follow these steps to soundproof walls in your home.
2007 Dorling Kindersley Limited
INTRODUCTION
The principles for soundproofing ceilings and floors from below can also be applied to walls. For example, you can fit hat channels directly to the surface of an existing wall. If losing a little space in the room is not a problem, build a completely new, independent wall in front of the existing structure. This is most easily done with a metal stud wall as it is quick and creates little mess. Build it 1 inch away from the original wall. You can then insert acoustic bat between the stud uprights to create a soundproof layer.
STEP 1
2007 Dorling Kindersley Limited
Using Hat Channels
Make sure that the open side of the ground-level channel is facing upward. In the others it should face downward.
STEP 2
2007 Dorling Kindersley Limited
Increasing Mass
Adding to the mass of a stud wall will help it to absorb sound. Adding blanket insulation will also improve its thermal insulation.
STEP 3
2007 Dorling Kindersley Limited
Adding an Independent Wall
When creating a metal stud wall, make sure that the acoustic bat is rigid enough to remain vertical between the metal studs.
STEP 4
Doors and Windows
Double glazing windows or glass doors improves sound insulation, as well as thermal insulation.
If noise from outside is a major problem, consider triple glazing.
Weatherstripping added around doors and windows will insulate them against sound as well as heat loss.
Soundproofing a CeilingLearn the two main methods of soundproofing a ceiling to reduce noise pollution in your home.
2007 Dorling Kindersley Limited
STEP 1
There are two main methods of soundproofing a ceiling. One is to use hat channels. These are lightweight metal channels that separate wall and ceiling surfaces, preventing airborne and impact noise from traveling through them. They provide a frame to which drywall can be attached. The other method is to lower the ceiling by building a false ceiling beneath the existing one.
In both examples shown below, the drywall of the existing ceiling has been stripped away first. An alternative to these is to fit hat channels directly onto the ceiling, in a similar way to that shown for walls. Where the existing ceiling is high enough to permit it, the second technique may be used, but without removing the drywall on the existing ceiling.
STEP 2
2007 Dorling Kindersley Limited
Using Hat Channels
Remove the drywall from the existing ceiling and attach hat channels across the joists at intervals of 16 inches. Fit acoustic bats four inches deep above these bars, between the joists. Attach two layers of drywall, one 1/2-inch thick, then one 3/8-inch thick, staggering the seams. Twin-layered board is available, and is a quicker option, but ultimately would be more costly.
STEP 3
2007 Dorling Kindersley Limited
Using Independent Ceiling Joists
Expose the existing joists and insert new ones between them. The lower faces of the new joists should be at least two inches below the faces of the existing joists. You should then weave a layer of acoustic quilt between the two joist levels, as shown, before attaching two layers of drywall to the lower joists in the usual way.
Build a Soundproof Wall by Natalina
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Up until recently, the only thing between my room and the one adjoining was a set of double doors. I like living with
people and do so by choice, but being able to hear someone's entire phone conversation word for word seemed a
little much. So I set out to build a more proper wall between us, and in the process learned quite a bit about
soundproofing. It worked out great, as now we can barely hear each other when talking at a normal volume. Success!
Step 1: Principles of Soundproofing
In planning what I was going to build, I needed to first understand more about soundproofing. I am by no means an
expert, but just learning the basics went a long way. There are 5 basic principles of soundproofing: mass, absorption,
conduction, mechanical decoupling and resonance. Read on for a brief overview of each principle and how I
addressed it.
Mass: This one is pretty straightforward. More density = more sound absorption. Thing is, you need it to be REALLY
dense to make a big difference, so simply adding a layer of drywall to an existing wall will only give you a slight
decrease in sound transmission. To address this principle I used two layers of the thickest drywall readily available
(5/8") vs the more common 1/2" thickness.
Absorption: Any kind of insulation within a wall's cavity will help absorb some sound, although it will not trap any low
frequencies. This is most effective when the walls are decoupled, as if there are studs connecting the two walls the
effect of the insulation will be minimal. Still, putting something in the wall is better than nothing, so I insulated my wall
with standard R-13 fiberglass insulation.
Conduction: This is the transmission of sound through vibration of solid objects connected to each other. Conduction
is a very efficient way to transmit sound, and as such any wall that has drywall directly connected to the studs on
either side will never perform well. Sound will also travel through indirect routes largely via conduction, and this is
called flanking noise. In my case I could do little to address this principle, as the nice solid doorway around my wall
would always be a good conductor of sound and the weakest link between our two rooms.
Mechanical Decoupling/Isolation: This is one of the most effective ways to combat conduction, and is why the most
effective soundproof walls are completely decoupled, so there is no direct path for the sound to travel. If not paired
with other soundproofing principles, decoupling a wall will help with transmission of mid-high frequency sound but will
increase resonance and sound transmission at lower frequencies (more on that below), so it must be done in
combination with other principles to be truly effective. To address this I kept my wall detached from the double doors
rather than attaching my framing directly to them, however I'm not sure if this made much of a difference considering
the conduction of sound through the surrounding doorway would probably outweigh any effort made on this principle.
Resonance: Despite best efforts on all of the above principles, sound will still resonate a well insulated, decoupled
wall if it hits the right frequency to vibrate the components of the wall. This isn't common in high frequencies, but is a
challenge for low frequencies (imagine how strong bass rumbles certain objects at particular frequencies, therefore a
decoupled wall will rumble x2 when the right frequency is hit for the mass of the wall). Not to fear, this is offset in two
ways:
• Lowering the resonant frequency of the wall: one can lower the frequency at which the wall wants to resonate by
making sure there is plenty of mass in each wall (tougher to vibrate), and by adding insulation / plenty of air in
between (absorption). This can help push the resonance point low enough that only the deepest frequencies will
vibrate through the wall. Sadly this is why your subwoofer will almost always annoy the neighbors, as these methods
can only push the resonant frequency so low.
• Damping: this refers to any means of reducing resonance altogether by absorbing or redirecting sound, and can go
a long way to combat resonance and conduction. By far the most effective damping agent out there is green
glue, and from all the specs I've seen it's likely the single most effective soundproofing aspect of my wall. I used the
compound to cover the area of my wall, and sealant to fill the seams.
Asleep yet? No? Great! If you're like me and found this all very interesting, here is some more reading on
the principles, and how decoupling works. Moving along, let's build a wall!
From study to studio, no-budget acoustic treatment by ArvidJense Download 9 Steps
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I recently moved into a new apartment and as a producer of electronic music, I wanted one of my rooms to have good
acoustic properties. But as a poor student, the budget for this project was nearly nill. I did some research on what I
could and found out that some simple modification can make a terrible sounding room into a decent room. When
finished I really felt like this was what happened. Some problems (especially in the low range) remained, but overall it
became a enjoyable room to record and mix in.
The next pages will tell you about my research and what I did to treat my room. You should be able to take the same
principles I've used and apply them to your own room.
Please note that I'm not an expert in this field and all knowledge presented is the result from some internet research.
If I've made any mistakes (even grammatical) I'd be happy to hear about them and correct them!
Step 1: Research
So, better acoustics in a room, while spending as little money as possible. Not the easiest task, considering most
professional studios spend several thousands getting the desired acoustic properties. To get a sense of the
possibilities, I grabbed some science and some internet research and made my own conclusions on it.
First thing to know is that sound is vibrations in the air, measured in vibrations per second, which is called Hertz,
shortened as Hz. Sound is often divided into three main categories:
Low 25Hz to 250Hz Tones you can feel as well as hear
Mid 250Hz to 2500Hz Tones in the range of the human voice
High 2500Hz to 25000Hz Tones you can easily block out by covering your ears
Each of these ranges have their own problems and can be fixed with specific objects as described later on in this
instructable. Common problems by having to much or too little of a frequency range are:
Low Bass tones which are boomy or disappear.
Mid Unclear sound where its hard to distinguish instruments or sharp/painful sounding music.
High A high pitched ring in the room, or a room sounding muffled.
So, what to do? Well, two two physics formulas shown, tell us the following
"The first parameter, ω0, is called the (undamped) natural frequency of the system . The second parameter, ζ, is
called the damping ratio. The natural frequency represents an angular frequency, expressed in radians per second.
The damping ratio is a dimensionless quantity." From: https://en.wikipedia.org/wiki/Damping
Ok, maybe not so clear. But what we can get from this, is that every matter will dampen sound and this is mainly
dependent on two factors. First is that each material will have a certain property that determines how well it can
dampen frequencies, and second is that increasing the mass (weight) will lower the dampened frequency. This is
actually quite intuitive; While a tissue might absorb some high frequencies, you need something like a mattress to
dampen lower frequencies.
With this in mind, I took a look at different websites such as
http://www.soundonsound.com/sos/dec07/articles/acoustics.htm
http://www.soundonsound.com/sos/feb06/articles/studiosos.htm
http://www.homestudiocorner.com/home-studio-necessities-8-acoustic-treatment/
http://www.gearslutz.com/board/low-end-theory/434479-studio-acoustic-treatment-low-budget.html
http://mediamusicforum.com/home-studio-acoustics.html
and of course https://www.google.nl/search?
q=low+cost+studio+treatment&oq=low+cost+studio+treatment&aqs=chrome.0.57j60j59j60j61j60.3744j0&sourceid=ch
rome&ie=UTF-8
With all this information soaking in, I started making a plan.
There are two main types of acoustic treatment and three frequency ranges to apply them on. Diffusers and
absorbers. Diffufusers reflect and spread the sound instead of bouncing it back like a wall does. Absorbers take in the
energy of sound and make it disappear. Both of these can be made for all three frequency bands.
Step 2: The Room
Every room is different, and so is the treatment it needs. My room is in a concrete apartment and as such, I had a
huge problem in the high range; When I'd clap my hands, there would be a one second pitched ring... Also the low
range was problematic as the sound pressure of certain bass notes were hugely disproportionate in different
locations in the room.
Some constraints are in the geometry of the room. Mine has a huge window I wanted to keep free, And there are two
doors an a big closet I couldn't put anything in front. Symmetry is important in getting a good sounding room, and my
room isn't. This means the acoustic treatment should play with this asymmetry to avoid worsening the problem and
rather balancing it.
Step 3: Design
It was obvious I'm not going to get get a professional studio, but I can improve the sonic characteristics by a huge
part. The best (aka most neutral rooms) are often so called "room within a room" designs, where you actually build a
second, free-floating room withing the actual room. But because of my tight budget, the small space and my desire to
keep the window functional, this was not an option.
I made a few sketches of what I wanted to do and finally came up with this design, see annotations. I'm putting
absorbers in place for all frequency ranges as well as doing some diffusion for the high range.
16x 100x30x10cm slabs of heavy rockwool (€10, I picked this up as leftovers of someones garage isolation project,
be sure to get the heavy stuff, the more weight per m3 the better. You can replace this by glass-wool or other
isolation material which are usually cheaper, but this was the best I could get for the price.)
4x 300x4x2cm beams of wood (€4, could be picked up for free, but I was impatient)
2x 150x50cm boards of hardboard (€4, similar)
10x randomly sized blocks of foam (free)
expendable fabric (free)
screws + plugs (€2)
random objects (free)
wires(free)
Managing bass is the hardest and most important part in acoustic treatment. The solution is to make a so-called bass
trap. There is a lot of theory on this, but the basic premise is to take a corner and stuff it half-full with isolation and
leaving half air.* Look at the pictures and annotations to see how I constructed mine.
*please let me know if you feel this is wrong, I'm not an expert!
Step 6: Building bass trap two
The second basstrap is similar to the previous, but instead of mounting a board in front of it, I just put some fabric in
front of it, so there would be no reflections at all.
Step 7: Building the high-mid absorbers
The mid absorbers were made by wrapping two pieces of rockwool in fabric and binding it with some string. The were
hanged on the ceiling just above my monitor speakers. Some space was left in between the ceiling and the absorber
to allow lower frequencies to bounce on the ceiling and return into the absorber.
Step 8: Building the high absorbers/difusers
The high absorbers/diffusers were made by stuffing blocks of foam with random objects. This allows the foam to
absorb some of the frequencies while the objects reflect and deflect some others. The block was wrapped in some
funky fabric to make it look a bit like a cloud. They were hanged in random locations on the ceiling to keep the room
sounding natural.
Step 9: Finishing up
With everything in place I could place my desk and monitor speakers again. Listening to some music I immediately
hear I made a big improvement in how the room sounds. Its not a perfect listening room, but most of the big problems
have been helped. There still are some problems in the lower end; I've got more sub-bass in the next room than in
the listening position. All in all, a great project to learn a bit on acoustics and to make this room my personal studio!
Soundproof Your Garage Walls (Using My Cleat Method) by mobilerik
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In this Instructable, I'll demonstrate how to soundproof a wall using a method I developed for my home recording studio. It is similar to the resilient channelmethod, but it is has advantages of being 1. much cheaper, 2.
much sturdier, 3. allows the possibility of securing shelves or heavy items to the wall, 4. is removable in case you'd
like to tweak something about it, and 5. uses ordinary 2x4 lumber that requires no special-ordering and associated
shipping costs. Compared to the resilient-channel method, one wall can be soundproofed to the same degree as the
resilient-channel method for about a fifth to a third of the cost. Sturdiness can be adjusted to your needs - for extra
precaution, you may simply "use more". (For reasons I'll describe, I prefer to use as little as I can get away with.) And
completely unlike the resilient channel method, you can drill holes in it (!) to secure heavy items such as shelves or
cleats to hang acoustical panels and the like.
The trick to this method is that the drywall panels are hung on a pair (or more) of wooden "cleats" made from a sliced 2x4. The upper cleat on the back of the drywall is isolated from the lower cleat on the wall behind by
inexpensive closed-cell foam tape. No part of the outer and inner walls touch directly. In practice, very little sound is
transmitted through the foam, and the walls achieve a very high degree of soundproofing. The weight of the drywall
keeps it in place so surprisingly well, that I use only two cleats: one near the top and one across the middle.
Overall, this method is fairly easy. It's not nearly as quick as using resilient channel, because it involves splitting a
2x4 lengthwise. (In either method, you will want to use foam tape to add extra soundproofing, so this extra step isn't a
tradeoff, unless you choose to buy the resilient-channel pre-taped. The parts list is very small - drywall, a table saw or
bandsaw, one 2x4 for every 4x8 drywall panel, nails, drywall screws, foam strips, and some pipe insulation.
Surprisingly, this method requires much less precision than you would think, because some mistakes are in a sense
self-correcting. Of course, the DIY version of this method does assume skill and confident use of limb-shearing power
tools to do a potentially-dangerous "rip cut". If you don't have a woodworker's confidence with this step, find someone
who can do it for you. A great recommended alternative is to have the lumberyard cut the wood for you upon
purchase. In the section on ripping the wood, I'll tell you what to say to get the cut we want.
Since soundproofing carries with it a lot of myths and misconceptions, this Instructable will start with a little soundproofing theory before heading into the steps.
Step 1: Soundproofing Theory
.
First I'd like to 1. clear up some basic soundproofing theory, and 2. explain some typical alternative methods.
"Soundproofing" (as distinguished from acoustical treatment) is concerned with blocking sound.
You block sound with 1. mass, and 2. isolation.
Putting foam or other absorptive things on the inside of the wall is not soundproofing, but acoustical room
treatment, which is used to reduce echoes and resonances and prevent excess sound buildup within a room.
Soundproofing and room treatment are completely different things. Room treatment improves the sound within the
same room. Soundproofing is about preventing sound from getting out or in. Definitely, putting foam on the
walls can help keep your neighbors from calling, but it's not because of "soundproofing" -- it's because you have
treated your room and in effect "turned down the volume" like they asked you to do.
Soundproofing a wall involves the principles of mass and isolation. A heavy wall will soundproof better than a
lighter wall of the same construction. BUT isolation is the trick that will let you achieve the same results with a lighter
wall.
A traditional wall involves panels (drywall, siding, stucco) connected to a frame, with drywall attached to the inside.
There is usually fiberglass insulation inside the wall. It can typically block about 30dB of sound if constructed tightly.
The way it works is mainly through the mass of the wall (drywall + frame) with some absorption by the insulation
(effectively "turning down the volume") in the little "room" between the panels.
You can make a better wall by finding ways to isolate one panel from the other. In the staggered stud method,
the vertical studs are staggered in depth so that the front and back panels are screwed into different sets of studs.
However, they are still attached to the same top and base board of the frame, so some sound will travel straight
through.
The ultimate method involves "double wall" construction. You essentially create a room inside a room with no
part of the inside wall touching any part of the outside wall. Double walls can block in the range of 55-60dB of sound.
A disadvantage is that the extra wall thickness can eat up a lot of space within a small room.
In between these two extremes, there is the resilient channel method, which involves attaching springy metal
strips to the studs of the outside wall, then screwing drywall into a flange on the strips in such a way that the wall can
flex against the resilient channel without touching the outside wall's studs. When constructed properly, these walls
can block into the 50dB range. Other implements can be added to the resilient structure to get into the high 50dB
range, such as foam tape and varieties of "isolation clips" that are clever ways to attach the channel to the studs
without screwing directly. Of course, the cost of these adds up quickly.
My method is also in between the single and double wall construction, and it is similar to the resilient channel method in creating a "springy" wall that will flex. Unlike the standard resilient channel method in which
the channels are screwed into both the stud and the drywall, in my method there is no direct mechanical path from
the outside wall to the inside wall. So my performance should be most comparable in soundproofing capability to
resilient channel methods with isolation clips. (Exactly how close we come remains to be verified by testing however,
so stay tuned for future revisions of this instructable.) I will say, however, that it's "pretty darned good".
Of course, if you're running a commercial operation or otherwise have the funds, definitely look into a well-
documented industry-standard soundproofing method like resilient channel or double-wall construction. They've been
studied and measured thoroughly, and there's little mystery about why they work and how well they work. But if you're
desperate and/or short on funds like many musicians, this method could be just what you need to get excellent
results without a lot of investment.
For more information on soundproofing, especially technical aspects of soundproofing and studio acoustics, I
recommend F. Alton Everest's booksMaster Handbook of Acoustics and Sound Studio Construction On a Budget. For
non-technical soundproofing advice (mixed with a lot of product hype) seeSoundproofing.org, (which I am compelled
to point out I have no affiliation with and am generally critical of, even though, quite coincidentally, they are local to
me.)
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