[daddydoom]

Recently I finished building  a home office/listening room combo and need some suggestion on where to start with the with the sound control. I live in Nashville TN and there are a lot of companies that build panels and do sound control, but what an attitude these guy's had. They made me so mad I decided to do this myself. I built the room. I could build and place these myself,with the help from you guy's.

The room is a studio quailty build. The floor is concrete with carpet. The walls are built with resilient channels, rockwool and dual layered wallboard. The ceiling is a drop ceiling with 1 inch tile,1/2 drywall and 6 inches of rockwool. The room (11 ft x 18 ft x 7' 6")

The question is where to start with the panels. I know you can over do it. I've read that you can not have too may bass traps. I seem to have more of a problem with the mid and  upper freqs. and slap echo. The lower freqs. have very little boom. I don't know if the wall are absorbing it or not. Since the panels are going to take some time for me to build, probably the rest af the year. Would it be best to start with bass traps or first reflection panels.

Matt

[MaxCast]

I'd start with first reflection and front wall.
Experiment with diffusion on the ceiling and back wall.
Load your corners with diagonally cut 2'x2' wool or fglass.

My room is constructed similar to yours, but my ceiling is lower.  I want to try diffusion up there soon.

[max190]

Matt
Are your spkrs setup on the shortwall?

[Ethan Winer]

The question is where to start with the panels.

My standard blurb follows. All rooms need:

* Broadband (not tuned) bass traps straddling as many corners as you can manage, including the wall-ceiling corners. More bass traps on the rear wall behind helps even further. You simply cannot have too much bass trapping. Real bass trapping, that is - thin foam and thin fiberglass don't work to a low enough frequency.

* Mid/high frequency absorption at the first reflection points on the side walls and ceiling.

* Some additional amount of mid/high absorption and/or diffusion on any large areas of bare parallel surfaces, such as opposing walls or the ceiling if the floor is reflective. Diffusion on the rear wall behind you is also useful in larger rooms.

For the complete story see my Acoustics FAQ.

There's a lot of additional non-sales technical information on my company's web site - articles, videos, test tones and other downloads, and much more.

--Ethan

[bpape]

Likely part of the reason you're not experiencing a ton of boom is the drop ceiling with insulation above.  While this doesn't provide as much in the way of isolation, it does provide some broadband bass control.  That said, additional in the front room corners and potentially on the rear wall behind the seating position are likely good candidates for additional bass control.

After that, I'd do side wall reflections and potentially the front wall behind the speakers if they have to be relatively close to the boundary.  Also, since the room is 11', you might want to experiment with a panel directly beside each speaker to help with boundary interaction.

Bryan

[daddydoom]

Thanks guy's

Max190,
   My speakers are on the short wall about 18 inches off the sidewall. I have a pair of Wilson Sofia's. with Bryston equip.

bpape,
   My back wall is a problem because this is my office and there is a lot of shelves and office related equipment. I'm hoping to build small bass trap cubes to set on some of the shelves. I have a lot of rockwool left over from the build. I ordered enough material from Guilford to try a lot of things.

maxcast,

    i will probably start with the first reflection. Just to tone the room down and work from there.


I do have another question. You mentioned cutting the rockwool on a diagnal which is what i have planned to do. What i want to know is if a square colum of rockwool in the corners would be any different given they both used the same amount of material. I was thinking of using square traps to keep the sides of the traps closer to the corner so they wouldn't look so large. This is my office and some clients do drop by. Most people I deal with do not understand why i am going to all this trouble. Sad isn't it.

My wife loves the sound proofing. I can play my music as loud as i want without disturbing family members. Life is good

Thanks again

[bpape]

12x12" squares will work fine.  It's actually the same surface area as a 17x17x24" triangle as far as what's exposed to the room.  It will reach down nicely too since overall, it has greater overall average thickness.  It's just not usually done since it sticks out in the room farther (17x17x24" only comes out 12" at 45 degrees to the corner)

Bryan

[daddydoom]

Thanks bpape

I am probably going to try the square trap. I just have to come up with a design.

Started my reflection panels Saturday and with some luck the GOM i ordered from GIK will arrive today so that I can see what my first will look like.

One more question

I have a drop in ceiling that has fine fissured 2x2 tile with a NRC of .70  15/16 thick with a 2x2 peice of 1/2 vinyl cover drywall and 5 inches of rockwool on top of that.

My question is should i need panels on the ceiling at the first reflection or do you think that the ceiling will absorb enough. I don't want to put anymore holes in the ceiling than i have to . Changing the ceiling tile out is not an option.

Matt

[bpape]

The NRC is an average and completely ignores the bottom end.  If you're asking about reflection control, then the tiles will likely be fine.  If you're asking about bass control over the seating position for height related modal issues, then you'd be best to remove the drywall from the tiles over your head and fill with insulation. 

I assume the drywall is there for isolation purposes so removal might not be an option.

Bryan

[daddydoom]

Yes the drywall is to block the sound. The reason is that the supply and return air duct are above me which was the hardest part of the build. The setup works great. Except for the concrete floor the entire room is decoupled from the house.

I plan on putting lots of panels and traps around the room. I will see how well that works first.

Thanks

[srlaudio]

I am located right here in Nashville!  Please contact me and you will have free on site analysis and advice....

[woodsyi]

You can stuff the corners above your drop ceiling with thick fiberglass batting for bass absorption.  My room is similar and I went with absorption in the front and diffusion in the back.  I like the sound I get.

Front:


Back:


I got GIK bass traps, Real Trap absorbers and SRL diffusers.  They all work well at their given tasks.   

[daddydoom]

Hey Allen,

I live close to brentwood. In a few weeks I should have my first reflection panels up and hopefully most of the bass traps will be made. Once that is done we can get together.

Speaking of bass traps. I will be building them soon and would like to know the difference between a corner trap that fills the entire corner or one that spans the corner. I am going from floor to ceiling with the trap. It seems to be easier to build one that spans and cheaper than a corner fill. It's to late to get cheap now, but if one is no better than the other. Some sort of savings would make the bank account a little happier.

Matt

[bpape]

Actually, if you make the spanning panel 6" thick and 2' wide, it takes the same amount of material as a triangular chunk of the same height.

The 6" panel straddling will reach slightly deeper but will also take up a lot more space in the room.  The rear of the spanning panel starts where the chunks would stop.

Bryan

[MaxCast]

Actually, if you make the spanning panel 6" thick and 2' wide, it takes the same amount of material as a triangular chunk of the same height.

The 6" panel straddling will reach slightly deeper but will also take up a lot more space in the room.  The rear of the spanning panel starts where the chunks would stop.

Bryan

What would both do?

[daddydoom]

Got my first reflection panels on the walls and ceiling today.

Wow

What a difference 6 2x4 panels make.

I can't wait until I get the corners filled. I can also see making all these traps taking a good bit of time, but if they make as much difference as the panels it will be well worth it. I have a few special conditions that are going to make building the corner traps a little difficult. So it may take a while.
 
I will post some pic's once I get a little more done. 



Matt

[daddydoom]

Finally finished most of the traps in my new office.

I need to work on the surface of the doors. I probably will try diffusors

It sure is nice to have it finally finished. Now I can start the never ending tweaking process.


Thanks for all the help

Matt