control room design, build, acoustics

[Gregwor]

Does it look good?

ALMOST! I think I know how you can get it 100%. Here is a spot you haven't ray traced and I believe would be a problem:

BETTER.JPG

If I were you, I would angle my soffits less... make them more perpendicular to the front wall. which would fix that one reflection from hitting your head area. I would make the front center section deeper for more insulation. I would angle the wings more. They could be a bit shorter yet to help achieve a greater angle. Your speakers don't need to be centered on your soffit -- It's actually recommended by some to NOT have it centered, so don't worry if it is offset after these adjustments.

I am amazed about how much you helped me. <3

Trying to help people like you is how I continue to learn, so thanks for coming here and asking!

Do you think i should do the same?

I was planning to cover the walls with gypsum board and behind put the insulation.

John Sayers invented what is referred to as "inside-out" construction. This is used when building a room in a room in which you build the inside room "inside-out". This leaves the studs exposed like in the picture you posted. It then allows us to fill the cavities between the studs with insulation and then put fabric over it. For a room in a room construction, it ends up saving a lot of material and space which is brilliant. This really shines for room in a room, inner room ceilings.

For your build, which isn't a room in a room, you very well could still build a frame inside your room to hold insulation and other treatment devices. Without getting to technical, we can consider your rectangular drywall room the dimensions for your room modal distribution. The rest of the stuff you put in your room is just acoustic treatment.

What are your concerns about tackling a ceiling cloud?

Greg

[konspan96]

Here is a spot you haven't ray traced and I believe would be a problem:

indeed, i ray traced it and it looks bad.

If I were you, I would angle my soffits less

Does they look wrong?
Doesn't that mean that my speakers angle will also change? shouldn't they be at 60 or 90 degrees?

here is a design with speakers at 60 degrees. Do you think i better place them this way?

I would make the front center section deeper for more insulation

Do you mean the space between the soffits? we can work on this later, lets finish designing soffits and wings first.

What are your concerns about tackling a ceiling cloud?

i am having a hard time designing the wings and soffits right now, ceiling and cloud can be the next step.

I would angle the wings more. They could be a bit shorter yet to help achieve a greater angle.

Ok, i made them shorter so now they are 5 degrees more angled. Does it look good now? Or would you prefer 60 degrees?


Note that the circle on the listening spot has diameter 60 cm.



(I also add the sketchup file in case you have some extra free time ) http://www.johnlsayers.com/phpBB2/downl ... w&id=68005

[Gregwor]

After seeing you struggle for so long I decided to just try and sort this out for you. I'm not sure how deep your speakers are but I drew the width and height the same as the speakers you had drawn. Also, note, I changed the units to feet and inches since that's what I'm familiar with. Also, I kept your inner dimensions but just assumed you might use 2 layers of drywall and 2x4 framing for your inner leaf.

With 30 degree soffits and short wings, you can eliminate any reflections back to the head sphere with ease. Your ceiling is pretty short though so it might not be as easy for the cloud.

Also, in your drawing you didn't make any components or utilize the layers. Components and layers are SUPER important when drawing in SketchUp. Also, google or youtube inference or inferencing in SketchUp. It speeds things up a lot and prevents moving things off axis. The last tip I'll give here is that you can completely draw up one speaker soffit and wing, then turn off the other layers (like foundation, inner leaf framing, etc). After that, select everything you want to copy over to the other side of the room (when the move tool is selected, hold option/alt while click and dragging --> note, use the arrows to lock to your axis while moving directly across the room). Then, use the scale tool and push in the middle handle, then type in negative one like this -1. It will flip the entire selection, making a mirror image of it to place on the other side of the room

I wasn't sure how deep your speakers are so I just took a wild guess when I drew up the speaker. Note, the distance the soffit baffle is from the front wall is very dependent upon the speaker depth because if it is too close, the back of the speaker will hit the inner leaf sheathing. The further you move the soffit baffle away from the front wall, the more you're going to have to angle the soffit so that the acoustic axis of the speaker aims at the tips of your ears. You don't have to be perfectly in line with the speaker as the speakers typically have a pretty wide horizontal dispersion. But be aware of it and adjust accordingly. With the short ceiling, you may find yourself needing to slide the entire soffit structure further into the room and this is when you might have to angle the speakers more.

Anyway, I think you get the idea. Here is a picture and the SketchUp file. Oh, and speaking of the SketchUp file, you posted a 2020 version. We all use SketchUp Make on here as it is the free version and it stopped being made in 2017. A lot of people use older operating systems so they might have much older versions on their computer. When you go to save a version for the forum, first go to model info, statistics, then purge unused. This will typically make your file small enough to post on here. If it is still too big, upload it to dropbox or your google drive or something like that that will hopefully be there forever. Then, go file save as and for the file type, choose an older version. For the one I uploaded I selected a 2014 version.

konspan96.jpg

konspan96.skp

Greg

[konspan96]

Greg you are so kind, thank you for all the help !
are you sure you want to keep designing the room with me?
I don't want to be greedy by asking so many questions

[Gregwor]

I'll help when/where I can. It's tough to make the time but I understand the anxiety of feeling lost but wanting and needing to get a project done. Luckily the search feature is great on the forum and chances are damned near every question you have does have an answer waiting for you on the forum. Don't hesitate to ask though!

Greg

[konspan96]

Hallo Greg

Just some questions about the walls so i can start constructing the frames.

I would like to ask about the kg of the rock-wool.

Because my room will be outside (next to) my house and temperatures here get really high in summer, i will also be using 4cm Styrofoam insulation.

So, from outside to inside i am thinking to go something like this: two layers of drywall -> Styrofoam insulation -> rock wool -> two layers of drywall (except rear wall that i am going to be using cloth to make the whole wall absorptive)

Does this order sound good to you? maybe you have an advice to make it better
What kg/m3 of rock-wool should i be using? The heavier the better?
Should i include a layer of empty space (air) inside the wall? If yes in what order should it be?

Thanks in advance

[Gregwor]

Because my room will be outside (next to) my house and temperatures here get really high in summer, i will also be using 4cm Styrofoam insulation.

I wouldn't use the styrofoam if I were you. It is closed cell so it won't help acoustically at all. If you have thermal concerns, you could just use higher R value insulation.

What kg/m3 of rock-wool should i be using? The heavier the better?

In the wall cavity, use whatever really.

Should i include a layer of empty space (air) inside the wall? If yes in what order should it be?

Maybe check your local building codes, but acoustically speaking, don't leave any voids.

Greg

[konspan96]

In the wall cavity, use whatever really.

How is that?
What about the rear wall that its going to be covered only with cloth ?

[Gregwor]

How is that?
What about the rear wall that its going to be covered only with cloth ?

Acoustic treatment inside your room is different than the MSM cavity. For the inside of your room, if you can afford and find Owens Corning 703, that is the good stuff.

Greg

[konspan96]

For the inside of your room, if you can afford and find Owens Corning 703, that is the good stuff.

I assume when you say for the inside of the room you mean for the back wall, bass traps, panels and stuff like that right?

[Gregwor]

I assume when you say for the inside of the room you mean for the back wall, bass traps, panels and stuff like that right?

Exactly.

Greg

[konspan96]

Today some of the framing was completed.

[Gregwor]

Even though I did that last drawing for you, I don't fully understand your build. But, I trust that you know what you're doing. It's just like building some Ikea furniture in that you have a detailed plan to follow

Greg

[konspan96]

No problem, actually we didnt need a plan for the outer frame but things are going good. As i said i am not going for a professional room.
Just wanted to share some progress
Next step -> outer ceiling frames

[konspan96]

hey Greg how are you ?
i have a question about the materials i should be using on my wings
i have seen people building them like resonators, others (under the speakers height) with cloth and insulation inside, and others just wall. What would you suggest?
The room is still being constructed, i am just working on it all day but i will post some photos soon.
Thanks in advance.