Angled walls,acoustic treatment or base structure- insideout

[PandPstudios]

Greetings to all of you!
This is my very first post in this forum after spending many months reading this amazing source of knowledge. Thanks John for creating this great community.
First of all sorry for my bad English you are about to read.
Well, as this is a very specific question I don’t think I have to specify every aspect of my project to get an answer to this. I’ve been searching for an answer for this around the forum and have come across them but I still kind of need to “hear” it directly.
The case is that I want to know how to correctly construct angled walls. In my project I’ve decided to go with John’s inside out system because of mayor space issues and don’t having THAT much budget for construction.
I will present different versions of the same and hope you can point me to the best of them.
Thanks in advance


1. You have your existing wall and constructed a new inside out wall on top of the existing one (imagine a 5” air gap between both filled with insulation)
To get the angled nature of the room I construct another inside out wall on top of that wall angled in say 6 degrees (insulation-gypsum-wood frames with insulation in the cavities and cloth to cover it all up).

2. You have your existing wall and constructed a new inside out wall on top of the existing one (imagine a 5” air gap between both filled with insulation)
To get the angled wall I build just a wood frame on top of that wall with insulation in the cavities and cover it up. No insulation in the cavity created by angling the wall 6 degrees.

3. Same as above just with insulation in the cavity created by angling the wall.

4. Construct the base of the room with the angled design, but there for wasting a lot of space behind these walls.




I hope you understand my different versions and chose one of them or tell me the correct one.
Another thing is that I don’t know if it would be necessary to cover the original structure wall with cloth even if it isn’t at sight.
I hope someone can help me out. Thank you.


Adolfo Gazzo

[Soundman2020]

Hola Adolfo, y bienvenido al foro! (De un vecino un poco mas al sur)...

Anyway, none of your options are correct! Option 1 is a three-leaf system, which is a bad idea, as it will reduce your isolation in the lower frequencies. Option 2,3 do not have any splayed wall at all, just a splayed cloth panel, which does nothing at all.

The correct way to splay your wall is like your option 1, but WITHOUT the first wall that is parallel to the existing wall. So you have your stud frame splayed at 6 degrees, and drywall attached to that on the cavity side of the frame, with the cavity (between the existing leaf and the new leaf) filled with insulation. They you have additional insulation, as needed for acoustic treatment, on the other side of that leaf, between the studs. The first insulation is part of your isolation (your MSM system), the second insulation is part of your treatment. Two different things.

It would help if you could provide a SketchUp model of your entire studio, so we can see what you are planning!

Saludos, y suerte con la construcción de tu estudio.


- Stuart -

[PandPstudios]

Thnx! for the fast response!

what you said is actually my option number 4. just that i didn't specify that the remaining space is filled with insulation. Soon i'm going to post the whole design in another topic. I just wanted to get as ready as possible before doing this.

Thanx (gracias)!!

Adolfo Gazzo

[PandPstudios]

After looking at some of john’s designs I’ve come across this case in which I can see clearly my 2nd option, have I misunderstood something? Please help me out because I think that in the alternative Stuart gave me (I do see it is correct and would apply it in case I had another adjacent room) is wasting too much “free” space behind the wall or should I maybe Use this space as something else. Just to clarify what I’m talking about I’ve added a quick sketch without dimensions or anything.

John's Design :




My doubt:




As you cans see another question appears Because of this doubt if I’m supposed to build hanger absorbers on the back wall isn’t it going to be automatically like in the second version?
I know and have read the post about being specific and ad as much info as possible but, in this case I just want to know the correct method of doing this not really applying it in my design.

Thank You
Adolfo Gazzo

[Soundman2020]

Adolfo, that's not the same as what you propose. You seem to be confusing isolation with treatment.

In the image that you posted, that is a slot resonator wall, not just a wall with insulation and cloth. That's a very, very different thing! See where the text says: "Inside out wall without gypsum and with slot resonator on top of insulation". It isn't really a "wall" at all. Yes, it is called a "slot wall", but it is not a "wall" in the sense of something that isolates the room from something else. So it is part of the room treatment, not the room isolation.

Isolation and treatment are two different things. First you need to isolate your room, and you do that with a two-leaf MSM system, which consists of two "leaves" of mass, decoupled, sealed, and separated by an air gap that is filled with insulation. The inner leaf can be rectangular, or it can be splayed. It depends on your design, and what you are trying to achieve.

Once you have the room isolation finished, THEN you can install the treatment, which MIGHT include slot walls, superchunk bass traps, membrane traps, absorption, diffusion, hangers, perforated resonators, other forms of Helmholtz resonators, gobos, etc, etc, etc. But the key point here is that the treatment is not part of the isolation, and the isoaltion is not part of the treatment. What you see in that image you posted is both isolation and treatment. The isolation is one thing, and the treatment is incorrectly labeled as an "inside out wall with no gypsum", but in fact that is NOT what it is! It is a slot wall, which is just a series of slot resonators arranged vertically on a frame, and set up at an angle from the inner-leaf of the room isolation.

In your bottom pair of diagrams, neither is correct: in both of them you are mixing up isolation and treatment. In the right-hand diagram, for example, all you have is a two-leaf isolation wall (which might or might not isolate very well, depending on what your needs are), then you have your treatment, which is just a framework holding some absorption in place, set at angles to the wall. That treatment won't do much, except to make the room sound a bit dull and lifeless.

The other diagram (bottom left) is a bit better, but you are cutting off the corners that you need for your speaker soffits at the front, and your bass trapping in the rear. If you were to build that room, you would have no place to install your most important treatment, since you already cut it off! You would also have no place to install your speakers, since you cut that off too!

Hope that helps!


- Stuart -

[PandPstudios]

Thank you very much! So if both are different things Treatment and Walls, what would you recommend? Building the walls as a common rectangle and then afterwards obtaining the designed angled "walls" with treatment. I do could normally point out the difference of both Treatment and wall, but in the conventional wall building method. But as I was looking at inside out design it kind of got me confused because the "wall" finish could end looking just the same as in conventional treatment methods, and I know that was actually the idea to use the cavities between the studs for treatment. But I guess I got it a bit mixed up it's a bit hard to get along a forum in a foreign language. Thanks

Adolfo Gazzo

[PandPstudios]

Sorry Bump. But i need to clear this out to continue with the project.

Thnx

[lilith_envy]

"Building the walls as a common rectangle and then afterwards obtaining the designed angled "walls" with treatment"
Yes

[PandPstudios]

Thanks Lilith for the concrete answer, I would do like to have some explanation of the benefits this work around gives. I’ve read your construction diary till now and noticed that you have done it this way. I have a little question regarding the back wall treatment. In case of installing Hanger Bass traps, what is the material exposed to the control room. In other words what is the final “wall” material for the rear wall? It is still related to my actual question because I want to know that if there is a kind of “hard” surface at these resulting “walls”, how isn’t this considered a three leaf system?
Thank you

Adolfo Gazzo

[jbassino]

"Building the walls as a common rectangle and then afterwards obtaining the designed angled "walls" with treatment"
Yes

Only if you go inside out. If you want hard surfaces in your room, you gotta build the angles directly from the isolation wall.
And slot walls aren't really considered as a third leaf

[Soundman2020]

In case of installing Hanger Bass traps, what is the material exposed to the control room. In other words what is the final “wall” material for the rear wall? It is still related to my actual question because I want to know that if there is a kind of “hard” surface at these resulting “walls”, how isn’t this considered a three leaf system?

The material is just cloth, stretched across a frame. It is not a third leaf, since it has practically no mass at all, is not a hard surface, and does not affect sound waves passing through since it has practically no gas flow resistance. You can use pretty much any cloth that you like, provided that you can breath through it very easily. Some people buy expensive acoustic cloth, other use muslin, others use anything they can buy cheap.

- Stuart -

[Soundman2020]

Adolfo, I'd suggest that you do all your designs in "SketchUp", whcih you get for free from Google. It makes it MUCH easier.

- Stuart -

[PandPstudios]

Thanks! to everyone who helped me out in clearing this doubt I had, now I can continue my design and will soon post something in the design sub forum! Including sketch up files of the whole project! Thanks again to everyone!

Adolfo

[blitz]

Hi lovely people,

this is my first post and pretty new to on-line forums. My friends and I are going to build a music production studio soon. The research we did pointed out that it is a good idea to have angled walls in the correct ratio instead of having parallel walls to get the best sound proofing and acoustic experience in the studio. Since we are new to this subject we are confused on creating the basic design of our studio. The room that we are going to build our studio is 18ft Long, 12 ft Wide and 9ft high. At the moment we have decided to have 11ft*12ft partition for the control room and 7ft*12ft(rest) for the recoding cubicle . Can someone help us to design our studio to get the optimal output. Hope you guys can help us succeed with our studio project. Your advices and expertise ideas will be highly appreciated. Thanks in advance.

Here I have shared the draw of the current idea. feel free to add your ideas. Cheers !!
https://docs.google.com/drawings/d/1KOR ... zq0os/edit

[Soundman2020]

Hi Blitz. Please start your own thread about your project, instead of adding it on to the threads of other people.

Also, please read the forum rules for posting (click here). You seem to be missing a couple of things!

- Stuart -