"The room is the most important component"
We've all heard that saying before, And while anyone who has heard their system in different rooms will usually agree, There is a line thats always drawn between form and function. Lets face it, Rooms with all kinds of acoustic treatments usually stimulate mental images of all kinds of ugly panels hanging from the walls, corners and ceiling leaving little room for any sort of design.
But ohhh, The tide is turning! More and more we are starting to see acoustic treatments which actually look GOOD! But one problem still remains, They are expensive. I did say the tide was turning though didnt I. Read on.
The design for these panels comes from the mind of a pretty well known character among audiophile circles, Especially DIY'ers, Known as John Risch. Here is a link to his website which contains the instructions for these panels among many other things you might find quite useful. Please also read through John's site as I havent listed every peice of information you should know before you build these. Its just a writeup of my experience building them.
http://www.geocities.com/jonrisch/index2.htm
Lets start with the most obvious first step for building these. Where are you going to put them and how big to they need to be? One very important thing to keep in mind here is the size of fabric that is available to cover them with. Following the directions on John Risch's site i went with burlap which i found at walmart. I suppose you could also use speaker grill fabric with great results and a bit better looking. Burlap isint exactly the nicest looking fabric and at the store and I was asked more than once just what I was going to do with it. Well, Knit a couple of sweaters for my parrot... What else?
Basic Materials Needed:
- Insulation. I reccomend 8" thick R25. I like the non backed but you may need backing depending how you plan to attach it. Roughly $20 per roll.
- Batting. Comes in various thicknesses and sizes. I got the thickest available which was 1/2 inch. Roughly $10 per roll.
- Burlap or other fabric that will allow for the most transmission of sound. The Black burlap I purchased was $1.90 at walmart.
- Frame materials. Your on your own here because there are so many different ways these can be made. Get creative!
- A radio to play some tunes while you build. A beer or two never hurt either.
Next you'll need to build a frame. The idea here is lightweight, Rigid and good looking. Your probably going to be hanging this on the wall so dont go overboard with the construction here. I used some leftover toe-kick peices which are an african mahogany veneer over some sorm sort of compressed sawdust like core. These are pre finished which was definetly a plus. Not to mention quite flexible. I formed the radius on these around a large wooden wire spool. Clamping it in place until i had braced the radius and fully assembled the rest of the frame so as not to distort the shape.
As you can see in the above picture i really wasnt doing any kind of fine cabinet making woodwork. Just throwing together a bunch of scraps, some glue and a few finish nails.
Next I threw down a layer of batting. You can find this at any fabric store or walmart etc. The only real thing its there for is to trap the fiberglass thats going into the panel in sortof a protective layer. I glued mine down with some 3m spray glue.
Next up is the fiberglass, I found some Owens Corning 8" R25 non backed insulation at lowes for 22 bucks a roll. I didnt realize it wasnt backed until I had unrolled it but I think its better that way, for the way I have assembled my panels because it doesnt have that extra layer of sound blocking material. I also thought i would have a hard time cutting the stuff but with a razor blade knife it cut extremely easily. I did not glue down the insulation.
The 3m Spray glue. This dries enough to hold quickly enough that i was able to pull the fabric on the panels when I put on the burlap without any use of staples etc to hold it in place while the glue dried.
After putting down the isulation I also layed down another layer of batting material to create my protective layer. I didnt glue down the batting on the top to anything I just tucked the excess down the sides. Next up is the burlap covering. I really didnt have a plan on how I was going to attach the burlap and all the most obvious ideas werent very do-able with the 1/4inch thick toekick material I used and the look I wanted to pull off. I ended up masking off the wood, spraying the top edge with the 3m Glue and simply gluing the fabric to the small top edge. It actually worked quite well. Getting back to what I said earlier about matching your panel with the fabric size, This is where I almost screwed up bigtime. I didnt take this into consideration when I built the frames and it wasnt until i went to get the fabric that i realized the only burlap available was only an inch bigger in width than my panels. This left very little room for me to play with when it came to stretching on and gluing the burlap.
I went back and trimmed off the excess burlap with a sharp razor creating a very clean and professional looking finished edge.
The finished product! Of course you can wrap the burlap covering around the sides and fasten it in the back but because of the nice mahogony wood I wasnt about to cover it up with some ugly looking burlap. The black and the wood are a nice compliment and match my speakers and rack nicely. I also had the choice of the more common beige/white burlap but find that color quite unattractive and too plain. The black is certainly more bold looking which may or may not be a good thing in your room.
I did some crude testing with the panels before I hung them on the wall by simply standing them up in front of my speakers, and the results were borderline shocking. These definetly absorb some serisous DB's across a very broad range. According to John Risch's findings they are good to about 100hz with the way i have constructed them.
To mount these I simply fabricated some little L brackets from some scrap metal strapping material used in home construction. There are tons of ways you can mount these.