John Sayers' Recording Studio Design Forum Archive

I produce and mix in my bedroom studio, I do not do any recording. My speakers are rather large and my room isn't very large and I would like to treat it to clean up the sound. Here is how it's laid out:
Here are a few details of the room:

It is 9 feet wide, 12 feet long, and has 8 foot ceilings.
The monitors are KRK Rokit 8" Generation 2.
There is a KRK 10s Sub underneath the desk (to the left of the chair, kind of in the center of the room).
Currently the window has a blackout fabric over it to keep sunlight out of the room
The entertainment center and dresser can be moved out of the room if they interfere too much.
The entertainment center is filled with a TV and books.

I recently got a Auralex Studiofoam Designer Kit (http://www.amazon.com/Auralex-Studiofoa ... B0002F78UI) as a gift and have yet to put them up.
It consists of 32 1'x1' panels
I understand that they aren't the most effective solution, but I have them and they were free.
I'm planning on treating behind the monitors, the side reflection points, and the window with the panels and placing the panels on foam board to mount them on the wall.

I have some questions:

Will the Aurelex panels be sufficient to get rid of the first reflections and should I be spacing them 1" from the wall to get rid of low frequencies? I'm planning on also putting broadband absorbers in the corners, or bass traps depending on what I need..

I need to control the bass. From what I read there are broadband absorbers and corner traps. Which do I need?
Are the traps built in this thread: http://www.johnlsayers.com/phpBB2/viewt ... 10&t=12321 what I'm looking for?
From what I understand, If I put plastic over the 703 that will make the broadband absorber in the corner only absorb the low end and not the high end. Should I do this since the aurelex panels will already be somewhat taking care of high end reflection?
Lastly, do I also need to treat the ceiling at all, or is that not necessary because I'm not doing any recording in the room?

I appreciate it, let me know if I failed to include any information!

Hi "sandaygo", and welcome!

Before you do any treatment, I would turn the room layout around 180°, so that you can get symmetry. It is critical that the front part of the room must be symmetrical, with your head on the centerline of the room, and the speakers spaced equidistant from the side walls and also from your head. If you don't have symmetry then the frequency-domain and time-domain responses will be different on the left and right, so your mixes will not "translate": Even though they sound fine in your room, they will not sound fine anywhere else, since you will have subconsciously "built in" corrections for these problems, so the mix will not sound right in all other locations.

So first get your symmetry problem resolved.

There is a KRK 10s Sub underneath the desk (to the left of the chair, kind of in the center of the room).

Actually, the general recommendation is to NOT have the sub on the centerline of the room. It is better to have it slightly offset to one side or the other.

The entertainment center and dresser can be moved out of the room if they interfere too much.

Excellent! That will make it easy to turn the room around! Put the bed where your system is set up right now, and center the system on that wall where the bed is right now, facing the window.

I understand that they aren't the most effective solution, but I have them and they were free.

You can't beat "free"! That kit won't do a lot, but it certainly can help a bit.

Will the Aurelex panels be sufficient to get rid of the first reflections

As I said above, they will help but they won't do the job fully. The recommendation you often see here on the forum is for 4" of absorption on first reflection points, spaced a few inches away from the wall. Your idea of sticking these on top of other absorption panels is good: that will help.

and should I be spacing them 1" from the wall to get rid of low frequencies?

On inch is better than nothing, but it won't give you much coverage in low frequencies. Low frequency bass traps need to be very large, and very deep, preferably a couple of feet deep.

I'm planning on also putting broadband absorbers in the corners, or bass traps depending on what I need..

It's a small room, so you will need LARGE bass traps. I would suggest that you could build your own bass traps, cheaply and simply, with panels of OC-703 insulation placed diagonally across the room corners, floor to ceiling, and use this foam kit just for ealing with flutter echo and first reflections.

I need to control the bass. From what I read there are broadband absorbers and corner traps. Which do I need?

It's the same thing: A corner trap actually is a broadband absorber. The simple ones I described above will work very well for a room like yours. One in each vertical corner will make a real difference for your low end.

Are the traps built in this thread: viewtopic.php?f=10&t=12321 what I'm looking for?

Exactly! The ones down at the bottom of that page are the best: triangles of 703 stacked in the corners. Those are called "superchunks", and are very effective. The method I described above is similar, but just using a single sheet of 703 placed diagonally across the corner. It works nearly as well as a superchunk, but costs a lot less as you need less 703.

From what I understand, If I put plastic over the 703 that will make the broadband absorber in the corner only absorb the low end and not the high end.

Correct. The plastic reflects back the shorter wavelengths of high frequencies, while allowing the longer low frequency waves through.

Should I do this since the aurelex panels will already be somewhat taking care of high end reflection?

What I would do is to first measure the room's acoustic response as it is now (after you re-arrange things to get symmetry, but before you put in any treatment). Do that using REW, which you can download for free. Then put in the basic treatment: corner bass traps with no plastic yet, the foam for first reflections, and a bit on the sides for flutter echo, and measure the response like that, to see what has changed and what still needs doing. Then decide if you need the plastic on the bass traps or not.

Lastly, do I also need to treat the ceiling at all, or is that not necessary because I'm not doing any recording in the room?

Sound wave move in 3D, not just 2D, so the ceiling is also a first reflection point. It is also the largest reflective surface in the room, and the ceiling-wall corners are just as bad for bass as the wall-wall corners. So yes, the ceiling needs treating too.

- Stuart -

Awesome, thanks for your welcome and your quick reply!

That helps a lot.

I'm ready to re-arrange my room but I just have one question about the arrangement. You said I should center the system on the wall and facing the window, do you mean I should be sitting with my back to the wall and the monitors pointing towards the wall as well?

I'm going to get the OC-703. I believe I can afford to make 9 broadband absorbers with 4" OC-703(2'x4'), framed in wood and wrapped in breathable fabric. I have not yet had a chance to search much locally for better prices on OC-703 so I might be able to afford more than 9 panels but I'll use this as the minimum I can get for my budget.

I was wondering what the recommended approach would be if I could only afford to build 9 broadband absorbers, Would this work?

1 panel in each corner
1 panel on each wall
1 panel on ceiling above monitors
+ the aurelex foam to cover additional wall

I know you said to put the panels in the corners floor to ceiling, would I be better off using 2 of them in each of the corners with an additional panel and the aurelex foam instead of the above method?

Thank you!

I'm ready to re-arrange my room but I just have one question about the arrangement. You said I should center the system on the wall and facing the window, do you mean I should be sitting with my back to the wall and the monitors pointing towards the wall as well?

I would do it like this:

Also note that the speakers have to come off the desk and onto stands behind the desk, and they also have to be rotated 30°, so they are pointing at your ears.

I was wondering what the recommended approach would be if I could only afford to build 9 broadband absorbers,

I would put one panel behind each speaker, between it and the front wall/window, one panel in each of the front corners (floor to ceiling), one on each side wall at the first reflection points, two on the rear wall, behind/above the bed, and the last one above the desk hanging from the ceiling, as a cloud.

And if you can double up on the corner panels, then sure! Go for it! The room needs a lot of bass trapping.

- Stuart -