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post #511 of 613 Old 07-16-2014, 04:43 AM
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Originally Posted by SteveS78 View Post
How low would my ceiling be lowered if I choose to decouple it from the joists?
There are several ways to do this... if you use Sound Clips & Hat Channel... I think there are two ways...

The first way is about 2 1/8" lower.. you attach clips directly to sub-floor joist, and run hat channel perpendicular.

The second way, is more labor intensive, but you could likely do for about 1" lower... you would have to install 2x4 cross bracing 'up' in between the joists with teh bottom edge of the cross-bracing about 1" HIGHER than the bottom edge of the Joist. Then, when you install the 'clip', the 1 1/8" deep clip, only 1/8" extends beyond the joist bottom. Then it is just the 7/8" hat channel depth.

I have seen other applications where people install entire new Joists in between their existing joist. This could likely be as little as 1/4" lower, but requires somwhere to rest the joists on (i.e., if building room within room, you would have the 'new walls', which the joist could rest on). If I am not mistaken, the guy who started this thread may be doing this method - you might take a look at his build (Ganroth, I think it is called the Phoenix Build).

Thanks!

Kevin


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post #512 of 613 Old 07-16-2014, 05:47 AM
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Thanks for the info. Does it make a difference as to what is above my basement in terms of making this decision? Right above where the screen and speakers will be is our family/great room that has a cathedral ceiling. Nothing is above that. The bedrooms are above the unfinished area of the basement with a floor in between of course. The floor of the family/great room is carpet and the kitchen is also directly above part of the finished area, just a little bit to the right of where the screen and speakers will be. It has a plastic laminate floor. Hopefully those surfaces (carpet and laminate) will help a little bit with sound.

I just looked last night, the pink R13 Owens Corning insulation is in the walls and they have stuffed that same insulation VERY thickly (10 inches) between the joists. It looks very sufficient. Its so thick its almost busting out in a few spots. Haha. Also, he just insulated the ceiling area above the speakers and screen. The area to the right of that is going to be a play area for the kids (just an open area), and I have chosen not to insulate that. I am sure some sound would escape there. We also have a stairway that already has a finished drywalled ceiling with the door to the upstairs. I am sure some sound would escape there too.

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post #513 of 613 Old 07-16-2014, 09:54 AM
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Quote:
Originally Posted by SteveS78 View Post
How low would my ceiling be lowered if I choose to decouple it from the joists?
Depends on how you do it. If you run new decoupled joists from the side walls, you can manage fractions of an inch depending on how accurate/brave you are with the measurements. Myself I lost about an inch, but I also went for more drywall layers than originally.

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post #514 of 613 Old 07-17-2014, 07:01 AM
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Originally Posted by kmhvball View Post
There are several ways to do this... if you use Sound Clips & Hat Channel... I think there are two ways...

The first way is about 2 1/8" lower.. you attach clips directly to sub-floor joist, and run hat channel perpendicular.

The second way, is more labor intensive, but you could likely do for about 1" lower... you would have to install 2x4 cross bracing 'up' in between the joists with teh bottom edge of the cross-bracing about 1" HIGHER than the bottom edge of the Joist. Then, when you install the 'clip', the 1 1/8" deep clip, only 1/8" extends beyond the joist bottom. Then it is just the 7/8" hat channel depth.

I have seen other applications where people install entire new Joists in between their existing joist. This could likely be as little as 1/4" lower, but requires somwhere to rest the joists on (i.e., if building room within room, you would have the 'new walls', which the joist could rest on). If I am not mistaken, the guy who started this thread may be doing this method - you might take a look at his build (Granroth, I think it is called the Phoenix Build).
I must have been sleepy... the Clip + Hat Channel is 1 1/8" drop if installed directly on floor joist.

Doing the Cross Bracing, you run the channel parallel to floor joist, and the recommended gap is 1/2". So, you 'gain' 5/8" for that extra labor/ time & material. I think doing a room within a room, could likely even bring that 1/2" lower.

Thanks!

Kevin


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post #515 of 613 Old 07-17-2014, 03:05 PM
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Quote:
Originally Posted by SteveS78 View Post
How low would my ceiling be lowered if I choose to decouple it from the joists?
If you decouple your ceiling with hat channel and clips and use double dry wall with green glue your ceiling will be lowered by 2".
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post #516 of 613 Old 07-20-2014, 10:11 AM
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Originally Posted by Nightlord View Post
Depends on how you do it. If you run new decoupled joists from the side walls, you can manage fractions of an inch depending on how accurate/brave you are with the measurements. Myself I lost about an inch, but I also went for more drywall layers than originally.
Isn't each layer of fire-rated drywall 5/8 inch thick? If you had two layers, you'd be at 1-1/4 inches, and that's with no clearance from the ceiling. Add half an inch for clearance, and you're at about 2 inches lost.

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post #517 of 613 Old 07-20-2014, 10:46 AM - Thread Starter
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Okay, let's start with a "typical" ceiling consisting of one sheet of 1/2" drywall directly screwed or nailed into the joists. That's our baseline.

Let's now replace that 1/2" drywall with 5/8" Type X drywall. Net loss is 1/8" and it gives us marginally better soundproofing.

Let's add another sheet of 5/8" Type X drywall. Now we have Joist + 5/8" DW + 5/8" DW, giving us a net loss of 3/4". The soundproofing is now notably better than the baseline.

Why not add a layer of Green Glue in between the drywall? The thickness of the material shouldn't change in any easily measurable way (save using a micrometer) but the sound reduction will be noticeably better than even the standard double layer.

But now we'll kick it up a notch and decouple, in addition to adding mass. This is where the true bang for the buck kicks in.

The least amount of lost vertical space would be to create floating joists between your existing ones -- but this does assume that you also have floating walls (a "room within a room" construction method). You'll lose around 9" in each dimension for width and length of the room. In theory, you could create your new joists and new walls to be maybe 1/8" below your existing joists. That would give you a net loss of 7/8". That would assume some pretty straight existing joists, though, and that's not been my experience. It's probably safer to assume around 1/4" clearance, which creates a net loss of 1". This will be your close-to-ultimate soundproofing solution (and not just for the ceiling).

You could get a similar amount of lost vertical space by offsetting clips and channels into the existing joists using blocking. See this illustration from the Soundproofing Company:



This gives you roughly identical vertical loss as the floating joist solution. It has very similar soundproofing capabilities to the floating joist solution, albeit costing a bit more and not addressing the walls or flanking.

If all that seems to finicky, then the standard solution is to use 7/8" clips and channels with the two layers of 5/8" Type X drywall (and Green Glue). Net loss there is 1-5/8". It has the same excellent soundproofing abilities as the "blocking" solution, but far easier to install and only giving up a maximum of 5/8" more.


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post #518 of 613 Old 07-20-2014, 10:56 AM
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Quote:
Originally Posted by ctviggen View Post
Isn't each layer of fire-rated drywall 5/8 inch thick? If you had two layers, you'd be at 1-1/4 inches, and that's with no clearance from the ceiling. Add half an inch for clearance, and you're at about 2 inches lost.
We only have 1/2 inch drywall here (12 or 13mm ) afaik, and I've never heard of it being fire-rated or not. But most of all, I had a layer of wooden beams perpendicular to the joists in the original ceiling that I didn't do now, so I saved a little space.

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post #519 of 613 Old 07-27-2014, 04:46 AM
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Originally Posted by Nightlord View Post
We only have 1/2 inch drywall here (12 or 13mm ) afaik, and I've never heard of it being fire-rated or not. But most of all, I had a layer of wooden beams perpendicular to the joists in the original ceiling that I didn't do now, so I saved a little space.
Sounds good. This is fire rated drywall:

Article about fire rated drywall

It's commonly used for sound transmission since it's heavier than normal 1/2 inch drywall. The 1/2 inch is about 1.6 pounds/ft^2 (square foot) and the 5/8 inch is 2.2 pounds/ft^2. A 4x8 foot sheet of 1/2 inch is about 51 pounds while the 5/8 inch is 70 pounds. I was used to carrying the fire rated, 5/8 inch stuff around, then picked up a 1/2 inch sheet and couldn't believe how light it was.

Bob
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post #520 of 613 Old 08-01-2014, 11:53 AM
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Does anyone have a suggestion for how to attach a baffle wall to a soundproofed room with clips and hat channel on the walls and ceiling? If I attach it to the hat channel will it cause a problem with room acoustics?
Thanks
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post #521 of 613 Old 08-01-2014, 08:28 PM
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I have a media room in a completed house (studs and drywall). What are my options of soundproofing the media room?

Can I just put another layer of drywall on top of existing drywall using super glue? My room is 12ft so I don't want to lose too much of width.

Do I have to remove the current drywall to use the clips solutions?
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post #522 of 613 Old 08-01-2014, 09:38 PM - Thread Starter
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Quote:
Originally Posted by smuggymba View Post
I have a media room in a completed house (studs and drywall). What are my options of soundproofing the media room?

Can I just put another layer of drywall on top of existing drywall using super glue? My room is 12ft so I don't want to lose too much of width.

Do I have to remove the current drywall to use the clips solutions?
Using clips absolutely requires removing your current drywall. Putting clips on top of drywall creates a "triple leaf" effect, which would make things notably WORSE rather than better.

If removing the current drywall isn't an option, then yes, installing another layer of drywall will make a difference. Get 5/8" Type X (fire rated) drywall; apply a layer of Green Glue to the back; and screw it into the studs on top of the existing drywall. That'll be notably better than what you have now.

But... if space is the primary issue and not cost or effort, then I'd strongly recommend removing the existing drywall. It's probably 1/2", which is quite a bit worse than 5/8" Type X. With the drywall down, you can also put in R-13 insulation between the studs. Then, you can also install clips and channels, which won't take up a huge amount of space (and could take up even less if you recess some support baffles -- see a few posts above this). The combination of all that would be worlds better than just adding one layer of drywall + GG.
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post #523 of 613 Old 08-04-2014, 10:06 AM
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SPL vs Loudness

What is measured by instruments is SPL [Sound Pressure Level, 0db = 0.0002 dynes per square CM, usually defined at 1kHz.]. Loudness is what we perceive by hearing, and it is not at all linear with SPL. To confuse the two is a serious mistake.

0.0 dBspl can be heard only by the most sensitive ear in an anechoic chamber.

The logarithmic dB scale relative to power is approximately as follows. 3dB is twice and 10 dB is 10 times. And, for example, 13 dB is 20 times, etc.

On a quiet day the average SPL outside might be 40 dB.

An SPL of 110 dB is considered the threshold of pain, and anything much above that [eg, rock concert] can risk damage to hearing.

A quoted post [somewhere herein] gives the range of sound on a soundtrack as ranging from 22 dB to 105 dB, and I'm pretty sure this is SPL, but was confused with 'Loudness'.

A lot of lab tests have been run on a persons perceived loudness, eg, Fletcher-Munson curves, since modified, as it's a complicated problem to quantify. So to avoid a lot of physics involving air temp and density, sound frequency, etc, I use the following rules of thumb.

3 dB increase in SPL is about the smallest change a person can reliably detect.

And a 10 dB SPL increase is what it takes for the sound to be perceived as twice as loud. YMMV.

When listening to music, I use the "Vacuum Cleaner Rule". If I am vacuuming my home theater whilst listening to music and I can still hear the vacuum cleaner, I turn up the volume.

Still, you should avoid SPLs above 110 - 113 dB. If it starts to hurt or go non-linear, turn off the vacuum cleaner and readjust.

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post #524 of 613 Old 08-04-2014, 11:03 AM
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Quote:
Originally Posted by kmhvball View Post
There are several ways to do this... if you use Sound Clips & Hat Channel... I think there are two ways...

The first way is about 2 1/8" lower.. you attach clips directly to sub-floor joist, and run hat channel perpendicular.

The second way, is more labor intensive, but you could likely do for about 1" lower... you would have to install 2x4 cross bracing 'up' in between the joists with teh bottom edge of the cross-bracing about 1" HIGHER than the bottom edge of the Joist. Then, when you install the 'clip', the 1 1/8" deep clip, only 1/8" extends beyond the joist bottom. Then it is just the 7/8" hat channel depth.

I have seen other applications where people install entire new Joists in between their existing joist. This could likely be as little as 1/4" lower, but requires somwhere to rest the joists on (i.e., if building room within room, you would have the 'new walls', which the joist could rest on). If I am not mistaken, the guy who started this thread may be doing this method - you might take a look at his build (Ganroth, I think it is called the Phoenix Build).
Sir,

I am not sure this is the place to post this but the problem I have in my HT is air conditioner noise, mostly mechanical rather than due to air flow. Short of turning it off, I can't figure any solution. I can treat the inside of flow tunnels/ducts, but with what and it's a fairly short run.

I've considered a diffusing effect by taking the air output [the source of the noise] and splitting it into maybe 3 paths [I have a little room, but not much] with some sound absorbent material on the inside surfaces - or something. Any effect on air flow must be considered.

Any thoughts world be appreciated.

Bill Wood
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post #525 of 613 Old 08-04-2014, 01:38 PM
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I am not real familiar with options, but using a Dead Vent might be an option, where you snake around flex duct in a 'box' (either outside the theater or in the soffit)... the 'snaking around' will likely require a larger diameter than you currently have as it reduces the air flow.

I went a different route all together and installed a Mini-Split AC/Heating unit, so, I didn't do too much research on the incoming air supply sounds.

Thanks!

Kevin


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post #526 of 613 Old 08-05-2014, 04:18 PM - Thread Starter
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Originally Posted by AeroA1 View Post
I am not sure this is the place to post this but the problem I have in my HT is air conditioner noise, mostly mechanical rather than due to air flow. Short of turning it off, I can't figure any solution. I can treat the inside of flow tunnels/ducts, but with what and it's a fairly short run.

I've considered a diffusing effect by taking the air output [the source of the noise] and splitting it into maybe 3 paths [I have a little room, but not much] with some sound absorbent material on the inside surfaces - or something. Any effect on air flow must be considered.
The gold standard solution for this is to create a Dead Vent as kmhvball mentioned. Here's a very good description of what that entails: http://www.soundproofingcompany.com/...the-dead-vent/

That link also talks about some of the concepts that that solution encompasses. I'm guessing that a dead vent might not be a feasible solution for you, so the next level is to look at the other aspects of the above design.

In particular, you'll ideally want to eliminate straight runs as much as possible and to essentially force the sound waves to run into absorptive paths. Using flex duct in a "snake" pattern running through insulation accomplishes this very well. The flex duct also eliminates vibration noises that can travel though rigid ductwork.

If using rigid (mostly straight) ductwork is required, then you can get decent results by lining the ducts with "duct board". Rigid ducts tend to be custom sized on installation, though, so there's a good chance that you won't have the space to work with.

(More dead vent discussion can be found here: Soundproof Ducting)


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post #527 of 613 Old 08-07-2014, 01:49 PM
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I have a HT in the basement, I'm not concerned with sound leaking into the other part of the basement, I just want to make sure it doesn't get upstairs.

In particilar the LFE. The wall I made separating the HT from the rest of the basement is a double wall - with approx. 9" of space in between (i.e. 3.5" for each 2x4 (filled with R-13) + 2" of air gap.)

I'd like to have the air from the rest of the basement be the "supply" for air into the HT. I have an 8" in line fan (also is 8" in length).

Can I simply bore an 8" hole near the floor from the HT out to the basement, and just rest the fan there?

What would this do to my sound isolation?

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Quote:
Originally Posted by cgott42 View Post
I have a HT in the basement, I'm not concerned with sound leaking into the other part of the basement, I just want to make sure it doesn't get upstairs.

In particilar the LFE. The wall I made separating the HT from the rest of the basement is a double wall - with approx. 9" of space in between (i.e. 3.5" for each 2x4 (filled with R-13) + 2" of air gap.)

I'd like to have the air from the rest of the basement be the "supply" for air into the HT. I have an 8" in line fan (also is 8" in length).

Can I simply bore an 8" hole near the floor from the HT out to the basement, and just rest the fan there?

What would this do to my sound isolation?

That's a 50sq in hole that you'd put through the wall, so a handy way to approximate the effect would be to open your door about 1/2" and play a movie. Does your open door leak enough noise to concern you? If no, then putting the fan in-line will likely be fine.

If it does concern you after your test, then you'll want to use that in-line fan in a "dead vent". You'll need two of them -- one for supply and one for return. See the post right above yours for some links on that very topic.


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post #529 of 613 Old 08-07-2014, 09:58 PM
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Originally Posted by granroth View Post
That's a 50sq in hole that you'd put through the wall, so a handy way to approximate the effect would be to open your door about 1/2" and play a movie. Does your open door leak enough noise to concern you? If no, then putting the fan in-line will likely be fine.

If it does concern you after your test, then you'll want to use that in-line fan in a "dead vent". You'll need two of them -- one for supply and one for return. See the post right above yours for some links on that very topic.
Thanks, I tried it and they couldn't hear anything upstairs!
Thx
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post #530 of 613 Old 08-11-2014, 07:54 AM
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I saw on the Ted's site instructions for the dead vent. In it he recommends putting a PVC pipe to go through the cavity of the wall to "contain the sound as it travels through the stud wall" (instead of regular metal duct),

however right afterwards he says it's ok to put a 16"x 16" flare - Why wouldn't this allow sound to escape as the metal flare has a large part of it in the cavity?
Thanks - just trying to understand this better
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post #531 of 613 Old 08-11-2014, 02:13 PM
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Because of the DW/GG/DW that your muffler is made out of. You are just looking at a slice of the top view at the room entry (or exit if return) the exit to the adjacent room is 6-8 foot inside the muffler that is insulated and sound does not like making bends. The entire muffler is DW/GG/DW so that is where the sound proofing is since you made a hole in the room's envelope.


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post #532 of 613 Old 08-11-2014, 02:31 PM
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Because of the DW/GG/DW that your muffler is made out of. You are just looking at a slice of the top view at the room entry (or exit if return) the exit to the adjacent room is 6-8 foot inside the muffler that is insulated and sound does not like making bends. The entire muffler is DW/GG/DW so that is where the sound proofing is since you made a hole in the room's envelope.
Why doesn't sound go up the wall (through flare transition) before ever getting into the muffler?
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post #533 of 613 Old 08-11-2014, 04:53 PM - Thread Starter
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Why doesn't sound go up the wall (through flare transition) before ever getting into the muffler?
To make sure I'm following you, you are saying that sound could get past the initial two layers of drywall in the theater by going into the 16" x 16" opening and then radiate upwards through the stud bay, between the drywall on the theater side and the dead vent on the other side. I suppose it could also radiate out to the sides, eventually bypassing the dead vent entirely.

Yeah, that is an alternate sound path. I haven't heard any indication that it's a notable one, though. You're going to have the wall sealed, so the sound can't travel through moving air. The wall boards are dense making it difficult for the sound to travel "up" it. That means it'll be traveling via the insulation and doing so at some 90 degree angles. That'll absolutely dampen the sound quite a bit.

I don't know that there are any empirical tests showing exactly how much of an impact all that has. I do know that from an anecdotal standpoint, the dead vent is used quite often and has a great reputation for working very well. That suggests that the sound loss is minimal.

Perhaps @Ted White or @BasementBob would pop in and give their expert advice on the topic (not sure if 'mentions' work in this version of the forum)...


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post #534 of 613 Old 08-11-2014, 06:43 PM
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To make sure I'm following you, you are saying that sound could get past the initial two layers of drywall in the theater by going into the 16" x 16" opening and then radiate upwards through the stud bay, between the drywall on the theater side and the dead vent on the other side. I suppose it could also radiate out to the sides, eventually bypassing the dead vent entirely.

Yeah, that is an alternate sound path. I haven't heard any indication that it's a notable one, though. You're going to have the wall sealed, so the sound can't travel through moving air. The wall boards are dense making it difficult for the sound to travel "up" it. That means it'll be traveling via the insulation and doing so at some 90 degree angles. That'll absolutely dampen the sound quite a bit.

I don't know that there are any empirical tests showing exactly how much of an impact all that has. I do know that from an anecdotal standpoint, the dead vent is used quite often and has a great reputation for working very well. That suggests that the sound loss is minimal.

Perhaps @TedWhite or @BasementBob would pop in and give their expert advice on the topic (not sure if 'mentions' work in this version of the forum)...

Yep that's what I mean, so if the between wall and dead vent loss is negligible m then likewise PVC would not be needed either
Again, just trying to understand
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post #535 of 613 Old 08-11-2014, 08:47 PM
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Why doesn't sound go up the wall (through flare transition) before ever getting into the muffler?

Two thoughts:


#1 ) The muffler area is a six sided box with two holes, one for air in, and one for air out.


#2 ) The linear slot vent diffuser is flush with the drywall, but the drywall will be stronger if there are sill framing (horizontal 2x4's, the same size as the studs, blocking the vertical wall cavity, flush with the top and bottom of the drywall cut out for the linear slot vent diffuser. A side effect of this is that it will stop some of the sound from going up the wall. The sill framing can be lined with duct liner on the airflow side.

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post #536 of 613 Old 08-12-2014, 08:33 AM
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Often in build threads I see soundproofing compared to a fishtank as sound leaks like water. I have to question this analogy because the sound that is stopped from passing won't flow to a leak point the same way water will, right? It makes it seem like if everything isn't done perfectly then it will not work.

This leads me to my question. I am trying to gather information for my build of which I am close to starting and on soundproofingcompany.com solutions #4 and #5 is what I was considering doing with my proposed space. However, I will not be able to do this over the entire room; 2 joists have HVAC runs, 1 has a water pipe that I think I will be able to work around and then the back of the room has a HVAC trunk i have to contend with. Without being able to do a solution #4 or #5 to then entire room would it still help me with most of the room done that way or should I just do more of something along the lines of #3 ?
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post #537 of 613 Old 08-12-2014, 08:51 AM
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I would like to know you opinion...

what would be the most efficient soudproofing for the money?

I would like to achieve a reasonable level.

I was thinking insulation between studs, 2 gypsum with green glue...samething for ceiling.

is Green Glue expensive?

My theater will be 8' x 15' x 23'
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post #538 of 613 Old 08-12-2014, 09:08 AM
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Originally Posted by Potatogod93 View Post
This leads me to my question. I am trying to gather information for my build of which I am close to starting and on soundproofingcompany.com solutions #4 and #5 is what I was considering doing with my proposed space. However, I will not be able to do this over the entire room; 2 joists have HVAC runs, 1 has a water pipe that I think I will be able to work around and then the back of the room has a HVAC trunk i have to contend with. Without being able to do a solution #4 or #5 to then entire room would it still help me with most of the room done that way or should I just do more of something along the lines of #3 ?
I assume you are referring to #4 & #5 of the "Ceiling" soundproofing...

Part of the benefit from #4 /#5 , i.e., drywall on the sub-floor, is that it helps with sound coming 'into' the theater. I would think that having it in most areas would help the footfall in those areas. I had a few similar issues, so, I went with #5 for my theater room. I did pull out the hard metal hvac pipes, and replace with Flex Conduit, which allowed me to place it on those sub-floors, and the flex conduit is suppose to help with sound getting upstairs as well.

I went with #4 in a downstairs bedroom, which is directly below my master bedroom.

The drywall on the sub-floor is on, the clips & channel are hung, and Drywall is supposed to start tomorrow.

Net, I HOPE it works... I'll tell myself it does regardless!!

Thanks!

Kevin


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post #539 of 613 Old 08-12-2014, 11:37 AM
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Originally Posted by Potatogod93 View Post
Often in build threads I see soundproofing compared to a fishtank as sound leaks like water. I have to question this analogy because the sound that is stopped from passing won't flow to a leak point the same way water will, right? It makes it seem like if everything isn't done perfectly then it will not work.

It would be more accurate to say that a $100,000 soundproofing job with a small defect, may be less effective than a $10,000 soundproofing job with no defects.
By way of example, there was a recording studio that was made out of two very thick six sided prefab concrete rooms, one inside the other mounted on precisely engineered springs. A broom handle fell between the two, bridging the gap, and what had been a 100dB separation dropped to a 50dB separation. They removed the broom handle and isolation was restored.
In our world, the most common example is shorting clips (resilient bars or acoustic hangers, where the mounting screws go right through the clips and into the stud), when installed by contractors who don't actually know why they're doing it or what attention to detail is required.

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post #540 of 613 Old 08-12-2014, 04:18 PM - Thread Starter
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I would like to know you opinion...

what would be the most efficient soudproofing for the money?

I would like to achieve a reasonable level.

I was thinking insulation between studs, 2 gypsum with green glue...samething for ceiling.

is Green Glue expensive?

My theater will be 8' x 15' x 23'
The bang for your buck levels of soundproofing goes in this order (IMO): Decoupling, Mass, Absorption, Damping

Doubling up on drywall is adding Mass. Insulation between studs is adding Absorption. Putting Green Glue between the drywall adds Damping. So far, so good.

But you're missing Decoupling, which is going to give you far greater gains than Absorption (alone) and Damping. You'd need two buckets of Green Glue for a theater your size, which would run you about $550 (give or take, depending on where you get it from and where you live). If money needs to be strictly budgeted for this, then I'd spend the money decoupling the room before I'd spend it damping the drywall.

Personally, I'd strongly suggest doing all four elements to truly repeat the benefits of them all working together. If you do drop one, then drop the Green Glue and spend that money decoupling the walls and ceiling.


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