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January 9, 2013 at 6:48 PM #53386jumpymonkey9Participant
A friend and I built a white room studio to use for some videos we will be putting online. We built it in his basement, and it's basically just drywall on 3 walls and on the ceiling. The part that's covered by the drywall ceiling and the right wall is about 8 feet, and then the floor and the left wall is 16 feet, and the back wall is about 11 feet. We have this big open area on one corner of the room. I guess you can say we've made a cave in one corner of his basement.
Is there a somewhat simple way to deaden the echo that we get when standing under the ceiling? The ceiling isn't in the shot, so we can hang something from there if that's what it takes. Or if we're just screwed because we needed to do something before putting the drywall up, please let me know. Thanks for the help!
January 10, 2013 at 9:06 AM #205602paulearsParticipant
The drywall is refective – that's what you're using it for, so if you've actually got two of them parallel, then sound will be bouncing around all over the place – parallel is bad in general. With these fixed and pretty permanent walls, you will have to treat all the other surfaces. Plenty of products on the market, many foam based and pretty expensive. The thinner, the less effective at low frequencies. For somewhat ugly and rough and ready results, cheap man made fibre filled duvets, heavy blankets and other devices can be used. You can put battens on the ceiling with duvets above, and these will soak up much of what comes off the floor, and covering all the walls in similar materials can help no end. Not as good as professional sound treatment – but hugely better than hard walls.
Google studio sound treatment – it's a common request for home studio people, and video has just the same issues.
If you need to Google proper solutions then
Absorption, refection, refraction, damping, membranes, traps and resonance will bring back useful info.
Some sound treatment is HUGELY expensive – but the coefficients are itemised so you can see which materials are best. Drywall, in thicker layers, is actually pretty good for stopping sound travelling through it because it absorbs very little – but of course this means it's also very good at reflecting! Soundproofing and sound treatment are very similar in some areas but different in others.
January 10, 2013 at 11:22 AM #205607jumpymonkey9Participant
Paulears, thanks for the reply. You've given me some good places to start. Sometimes if you don't know the right terms to google you can't get the info you need.
I think we could hang something from the ceiling, but we need the rest of the walls to be empty. It's meant to be just a big white space. Since the drywall on the ceiling isn't in the shot, I guess we could just take it back off, even though that would be a pain to do.
January 12, 2013 at 12:50 PM #205622
[quote=jumpymonkey9] Or if we're just screwed because we needed to do something before putting the drywall up, please let me know. Thanks for the help! [/quote]
A simple and inexpensive method to solve that problem is to get your hands on some Owens Corning 703FRK. If you don’t mind the look you can just hang these panels on the walls as well as place a few of them upon the ceilings, if you want to get fancy you can fabricate some 2” pinewood frames and wrap the frames with upholstery or drapery fabric.
This is an example of how to frame OC703FRK and yes the FRK is on the back which seems backward but I have found them to work better that way.
I have never dealt with this company but this is an example of OC703FRK.
FWIW their prices seem a tad bit high, I sourced the OC703FRK locally for $75 per box of 6, you can go to the OC web site and maybe find a local dealer of the product and save on both actual cost and shipping.
I can tell you this without a doubt the panels do work and work very well.
I have used them in a few broadcast studios and they can make a room totally dead and dollar for dollar even if you build your own frames they are half the cost of a product such as the Auralex wedgies.
Now I am assuming (and that’s a dangerous thing to do) since you stated your studio is in the basement as in below the ground, that you are not concerned with sounds coming through the walls, however if you do need to block through the wall sounds then there are two important things to remember, dampening and coupling.
Dampening is used to reduce the amount of sound that will pass through the wall and reasonable dampening can be had by stuffing the wall cavity with good old fashioned yellow or pink fiberglass insulation, if you have a fatter wallet rock wool does an even better job but at a price.
Coupling is the sound transmitted through the wall by the 2 by 4 studs, one side picks up the sound like a microphone diaphragm and the 2×4”s “couple” it to the other side turning it into a speaker cone.
The solution is to double up on the number of 2×4 studs and offset them a half inch out from the edge of the header and footer and a coupe of inches apart from each other while remaining on 16 inch centers, this allows each side of the wall to be hung from it’s own studs without any through wall coupling to the other sides studs.
January 13, 2013 at 3:26 AM #205630paulearsParticipant
There's a big difference between sound treatment and sound 'proofing'.
Your drywall makes the room sound 'boxy', and I'm thinking this is what you don't like. Transmission of sound through the dry wall works both ways – it essence, it leaks sound through. In your case, you've not mentioned sound is getting in from outside, or indeed that your sound is leaking elsewhere?
You'll see from research that in most cases, mass is the key – my studios that I've built over the last fifteen years have gradually standardised onto a successful system that balances effectiveness against cost. The product titles are different here, but my current designs have MDF as the inside sheet. Behind this is plasterboard, then insulation board (as in the material that you use as pinboards to stick up notes on walls)then an inner plasterboard sheet. It's quite thick, but works very well. Usually the timber behind supporting it is 3 x 2. This seems to offer a good balance of performance v cost (and weight!)
The plasterboard (drywall) does mean that the room is very reflective – especially with 5 surfaces covered in it, and that's when you need treatment to stop all this reflection. Usually it's HF reflections that mess with the sound, but sometimes thinner drywall on wider spaced studs creates resonance – strange low frequency humps in the room frequency response which need bracing and sorting out properly.
January 12, 2013 at 12:59 PM #205623
[quote=jumpymonkey9]I think we could hang something from the ceiling, but we need the rest of the walls to be empty. It's meant to be just a big white space. Since the drywall on the ceiling isn't in the shot, I guess we could just take it back off, even though that would be a pain to do.
On the cheap you could hang the FRK on the walls silver side out and paint it white and it will work and since it is out of sight just screw the panels to the ceiling.
January 13, 2013 at 5:33 AM #205631
There's a big difference between sound treatment and sound 'proofing'.[/quote]
While there is a difference they both share common solutions.
[quote]Your drywall makes the room sound 'boxy', and I'm thinking this is what you don't like. Transmission of sound through the dry wall works both ways – it essence, it leaks sound through. In your case, you've not mentioned sound is getting in from outside, or indeed that your sound is leaking elsewhere?[/quote]
Based on the title the OP is complaining of echo, which is the result of having a hard room due to the hard reflective nature of drywall and the cure for that is sound panels or tiles.
[quote]You'll see from research that in most cases, mass is the key – my studios that I've built over the last fifteen years have gradually standardised onto a successful system that balances effectiveness against cost. The product titles are different here, but my current designs have MDF as the inside sheet. Behind this is plasterboard, then insulation board (as in the material that you use as pinboards to stick up notes on walls)then an inner plasterboard sheet. It's quite thick, but works very well.[/quote]
While adding mass lowers the resonant frequency of the walls, it does nothing to stop transmission through the wall. And while the corkboard will absorb a minor amount of pass through sound energy the fact that it is coupled to the supporting studs pretty much negates its use.
[quote]Usually the timber behind supporting it is 3 x 2. This seems to offer a good balance of performance v cost (and weight!) [/quote]
Two by threes are too small for this application and are and with the exception of mobile homes not allowed for wall construction under most building codes,
The very minimum for constructing an actual sound wall is to utilize a 2×6 header and footer with staggered 2×4 studding 16”oc.
For example a standard single stud residential wall is constructed like this.
The wall consists of a 2×4 header and footer with 2×4 studding 16” oc and even if filled with fiberglass will still couple sound from one side to the other.
To prevent coupling the studs need to be either staggered or double studded.
This is an example of staggered studding, note the 2×6 footer and of course the header have been ripped making it into a 2×4 and 2×2, the reason for the rip is to prevent coupling through the header and footer and while I have done this in after-the-fact remodels doing so will usually not pass inspection in new construction or permitted remodels.
As such the only “approved” method of decoupling a sound wall is to double stud it, that is to build two walls each one dry-walled on the outside and open to each other on the inside.
Now the difference in de-coupling between staggered studding and double studding is not all that great, as such if one can get away with staggered studding it is a considerably more economical solution, it just doesn’t meet code in most areas of the US. .
Now there is a third solution called Owens Corning Quitezone but it requires a considerably fatter wallet to implement.
Also any cutouts such as those for outlets and switches must never be made back to back within the same cavity as they will become conduits for sound.
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