Panel design feedback

From my limited knowledge of things, I understand that mid/high freq absorbers spaced from the wall will help with bass frequencies as well. Here is a pic of a panel box I designed. It will house two 2' x 4' panels to make a 4' x 4' panel with a 2" thick piece of rock wool or OC 503. I'm planning on using this to the left and right of my mixing position. I have it angled to give it a variable distance from the wall from top to bottom. The top is open to allow for equalization of pressure waves (not sure if I should enclose it all the way or not though...thoughts there?). Tell me if I'm totally off on this design....

Acoustics can be quite daunting because so little of it is intuitive. You have posted on this thread, so have read it. Re-read my first post in that thread. Do a bit of research on materials available locally, and you can probably make them for a fraction of the cost. I am assuming that the extra inch or two is not significant on the depth because you are already considering tapered designs using that space. Keep em coming! Andre

Thanks! I will look into what is available locally to make my decisions on what material to buy. If a certain material is close in properties and is one-fifteenth the price like it is for you, I will definitely go that route... Is my design above sound? Does the gap and use of only a 2" panel work? I'm actually planning on vaneering everything in cherry to match the desk I built - you can see the desk here: http://www.johnlsayers.com/phpBB2/viewtopic.php?t=10243

awilki01 wrote:

Thanks! I will look into what is available locally to make my decisions on what material to buy. If a certain material is close in properties and is one-fifteenth the price like it is for you, I will definitely go that route...

Look at the materials available, and use the the resources here and [/quote]here at at Bob Gold's excellent absorption data site

Is my design above sound? Does the gap and use of only a 2" panel work?

The design is sound. Gapping will cost you more than using lower cost materials completely, as I wrote in the linked thread.

I'm actually planning on vaneering everything in cherry to match the desk I built - you can see the desk here: http://www.johnlsayers.com/phpBB2/viewtopic.php?t=10243

I was admiring your desk a couple os days ago. Beautiful! Keep the questions coming. Talking (or posting) is a lot cheaper than doing it wrong and regretting it. Andre

AVare wrote:

The design is sound. Gapping will cost you more than using lower cost materials completely, as I wrote in the linked thread.

No worries there. I have room to put another 2" panel behind the top 2 x 4 panel should the need arise. If going with cheaper material, would you recommend this? The bottom panel doesn't have any room behind it to place another panel - perhaps a partial panel could fit...... Thanks for the responses! It is greatly appreciated!

awilki01 wrote:

. I have room to put another 2" panel behind the top 2 x 4 panel should the need arise. If going with cheaper material, would you recommend this? The bottom panel doesn't have any room behind it to place another panel - perhaps a partial panel could fit......

Great! A clear closed question. The answer is yes. Yes, I can write short posts, Andre

AVare wrote:

awilki01 wrote:

. I have room to put another 2" panel behind the top 2 x 4 panel should the need arise. If going with cheaper material, would you recommend this? The bottom panel doesn't have any room behind it to place another panel - perhaps a partial panel could fit......

Great! A clear closed question. The answer is yes. Yes, I can write short posts, Andre

Now, I'm wondering if I should even angle the absorber. If I didn't, I would have more room to put in material. And, it would be easier to build......

awilki01 wrote:

AVare wrote:

Great! A clear closed question. The answer is yes. Yes, I can write short posts, Andre

Now, I'm wondering if I should even angle the absorber. If I didn't, I would have more room to put in material. And, it would be easier to build......[/quote] We are on a roll now. :D Acoustically it is better to build it straight and thicker. Still short, Andre

Andre, I really appreciate it........ Thanks! Adam

Here's the new design. I figured I could build the panel out of 1/2" MDF or something else inexpensive and place them in a decorative box built out of 3/4" MDF with a cherry veneer on the outside to match my desk. Each panel would fit in the spaces in the surrounding box. I gave an additional 1/8" on the decorative box so as to make sure the panels fit with the fabric on them. I have corner supports in the panels so when I screw down the decorative panel to the acoustic panels, there should be no need for added support to the whole unit. I could have just created the decorative box and put the panels in them, but then the fabric would not have anything sturdy to pull against other than the rock wool/insulation itself. I think this will probably take more time than most people would spend on these, but I want them to look really nice. There will be about a 1" airspace gap behind the rock wool/insulation and the wall it will be hanging on. Should I have holes in the decorative frames to allow for airflow? I would think not, but I"m not sure..... Any ideas on how to hang these on the walls? This can all be used for panels on the walls, a cloud, and bass traps that straddle wall to wall and wall to ceiling interconnects. Please provide feedback if I need to change these in anyway. I've also added the Google Sketchup file....

The frames with no holes should be fine. I am somewhat confused about your remark about the 1" gap. If you have a gap, you will have to put something there to hold the absorbent material in place so that it does shift and change the acoustics of the room over time. My suggestion is to look for the best material for the money and build the frame to match the thickness. Please resize your pic so that it follows the guidelines. One of the greatest ways to ensure few responses is to have pics so large that people have to scroll back and forward just to read the text!

The frame supports will hold the fiberglass/rock wool in place. If you open the Sketchup file and rotate to the back, you will be able to see what I'm referring to. I will probably have to put in the supports a little closer to make sure they are firmly against the acoustic material. Resized the pics....thanks!

Thanks. Please that that many people do not use sketchup . I se what you are saying. What about the middle mass sagging? Don't get me wrong. It is great going from generalities to specifics! Andre

AVare wrote:

Thanks. Please that that many people do not use sketchup . I se what you are saying. What about the middle mass sagging? Don't get me wrong. It is great going from generalities to specifics! Andre

I'm not sure what you mean by the middle mass sagging. Isn't rock wool/insulation relatively rigid and able to support its own structure? Are you suggesting I put a cross bar across the back to support the middle as well? I wouldn't have thought it would be needed.

awilki01 wrote:

I'm not sure what you mean by the middle mass sagging. Isn't rock wool/insulation relatively rigid and able to support its own structure?

Relatively is the word. Are you going to risk it sagging in three or five years and changing the sound of your room? If you look at pro designs with gaps, they all have supporting structure behind them. You ignored the most important part of my post. That being get the best value for your dollar. Andre

I'm not sure how you gathered I ignored getting the best value for my money. That is my intention. What led you to think otherwise???

awilki01 wrote:

I'm not sure how you gathered I ignored getting the best value for my money. That is my intention. What led you to think otherwise???

Posts going in different directions from what was written in the thread, or several others that you have started or posted on. Keep asking! Posting is cheap, building and rebuilding isn't! Economically, Andre