Sound Proof Construction Techniques

[gage]

Hi All,

Bit of a random question but I am wondering if anyone has had experience using quietrock or Acoustiblok for the purposes of creating a quiet office/listening space?

www.quietrock.com
www.acoustiblok.com

Framing will be 24"OC double wall - steel studs and the ceiling will use hat channel run at 24"OC Insulation will be done with ROxul stone wool at 7"thick.

If anyone has any guidance for me or has created a hometheatre/studio space and done something different please let me know. The above is not going to be cheap so any suggestions is very much appreciated.

[mookieo2]

This is the best stuff around. Its also cheaper than Quietrock which is like $120 a board. Check out their site for installation and room construction techniques.

http://www.greengluecompany.com

We use it in all our theaters and it is used in mill$ THX certified home theaters. Double 5/8" on both sides of studs if possible, caulk every hole where a wire passed through, heavy solid doors with weather seal or locking acoustic door seal if you want to get crazy. Any untreated AC vents will be your downfall. If possible put in a diffuser and get the ducts lined.

[SacDuc]

How quiet? Is there a lot of outside noise that you have to block? Any exterior walls? Any windows or doors to the outside?

Are you engineering this room (will there be math involved) or are you just trying to get the room reasonably quiet.

Is the listening room for primarily one chair (a "sweet spot" in the room) or do you want the whole room to sound good?

mookie is right, HVAC can ruin a nice quiet room. How is the room conditioned and do you have the opportunity to up size the ducts?


sac

[herm]

cant be done

[Oldfisti]

Friend of mine built a home recording studio.  He built the walls with an 8" cavity using 2x4 studs staggered outside/inside and ran

the insulation horizontally, zig-zagging around the back side of the studs.  He lined the walls with a flame resistant egg-crate type

material.  Not sure of the actual product but he said the wall construction design was crucial for trapping and cancelling the sound

waves.

[jc.cyberdemon]

quite space huh? did you just have your van stolen?

[the_Journeyman]

Friend of mine built a home recording studio.  He built the walls with an 8" cavity using 2x4 studs staggered outside/inside and ran

I've heard of this used in a basement setting where support wasn't an issue.  The builder, after running all wiring and very carefully sealing all openings into the sheetrock, used sand to deaden sound.  Still leaves the ceiling to deaden.

JM

[mitt]

I've heard of this used in a basement setting where support wasn't an issue.  The builder, after running all wiring and very carefully sealing all openings into the sheetrock, used sand to deaden sound.  Still leaves the ceiling to deaden.

JM

offset 2x4's and combo offset 2x4 / 2x6 walls can be used externally as well for ultra high energy efficiency houses.

[Timmy Tucker]

<---- 15 years designing, building and working in recording studios.


Lots of good advice in this thread already. Mass and isolation are the keys to "soundproofing". And let's get this out of the way now... Egg crate has almost zero practical use in an acoustic application. It lacks the necessary density to diffuse acoustic waves under approx 15Khz. That's the average upper threshold of human hearing.

It you are designing/building the room from scratch, you can easily design it to be a fairly neutral listening environment. I prefer the an asymmetrical room for a recording environment, but they are a pregnant dog to design. DO NOT make the room a cube or use dimensions that are multiples of each other. You will end up with an uneven response throughout the room and very prominent standing waves. You can keep it simple by rectangular dimensioning according to the ratios below. They create a very even room response, which is the foundation for a great listening environment:

*note that these apply to the finished inside dimensions*

Heigh  Width   Length
1.00     1.14       1.39
1.00     1.28       1.54
1.00     1.60       2.33


Since this is a listening environment, you're gonna need to look at positioning. Speakers 3-4 feet minimum from any wall... more is better, if possible. Much closer and you will get resonance and reflections that contaminate your source sound. Speakers and listening position should form an equilateral triangle for accurate imaging.


Wall/room treatment varies wildly from case to case, so it's hard to comment on them. There are lots of options available now that weren't around 10 years ago, and many of them are aesthetically pleasing as well. You won't really know what you need until you have listened to the room. Basically, You want to minimize reflections in the listening area and mitigate standing waves/nodes, but on the other hand, you don't want to completely kill the room either. Rooms with a very short RT60 (Google is your friend here) sound dull and unnatural. I'd say shoot for an RT60 of .4 - .7 seconds if it's a normal house-sized room. That's about average for a control room, so make your listening environment similar to accurately reflect that. If the room is bigger, I'd shoot for .6 - 1.0 seconds. There are free RT60 calcs available online. When you get the room built, if you decide to treat/tune it post back up here or PM me and I'll give some more specific advice.


As far as the actual construction goes... make sure you are set with your electrical/wiring. Never a bad idea to plan ahead for future upgrades. The only thing worse than trying to soundproof a room is remodeling a soundproof room.

Decouple everything from everything else... decouple the gypsum from the studs, the wall from the floor (only if wall is not structural), I have built floating floors and decoupled walls from each other as well. Make sure any penetrations thru the wall are sealed very well.  
Use sealed or draft-proof electrical boxes and covers. FYI, a 1" hole measures just as many db's as an open door, given identical sound sources. So seal that shit tight!!

[Oldfisti]

^^^^^       


Great response!


       


(PS I don't think my friend used actual eggcrate material it was more of a purpose product)

[mookieo2]

If your building a theater or listening environment we use Gerry Lemay. He's a well known acoustic designer. For a great price he will give you a full acoustic analysis of the room with drawings of acoustic panels laid out and subwoofer positions( an extremely important part) you can contact him at WWW. Questai.com

[mitt]

<---- 15 years designing, building and working in recording studios.


Decouple everything from everything else... decouple the gypsum from the studs, the wall from the floor (only if wall is not structural), I have built floating floors and decoupled walls from each other as well. Make sure any penetrations thru the wall are sealed very well.  
Use sealed or draft-proof electrical boxes and covers. FYI, a 1" hole measures just as many db's as an open door, given identical sound sources. So seal that shit tight!!

How is decoupling actually accomplished from a practical standpoint?   For example, how do you hang gypsum board on the studs without coupling it?  Same for attaching walls to the floor.

mitt

[Grappa]

Soundproofing, hunh?

It puts the lotion on it&amp;#39;s skin

[mookieo2]

How is decoupling actually accomplished from a practical standpoint?   For example, how do you hang gypsum board on the studs without coupling it?  Same for attaching walls to the floor.

mitt

If you want the ultimate you build a room inside a room using rubber isolators to seperate( decouple) them from each other.

[SacDuc]

How is decoupling actually accomplished from a practical standpoint?   For example, how do you hang gypsum board on the studs without coupling it?  Same for attaching walls to the floor.

mitt

There are clips and rails specifically for this purpose. Here is an example:

http://shop3.mailordercentral.com/supersoundproofing/prodinfo.asp?number=09-AS-1S

Ceilings should be sprung and floating.

Floors are difficult. Thick carpeting DOES NOT HELP.

sac