[Mister Pig]

I suspect this topic has been covered before, so sorry for bringing it up again.

A few years ago I built some DIY wall treatments for my room. My listening couch is located against a wall, and I needed to deal with the reflections off of it.

Since funds were tight, I decided to DIY a set. I read a few home brew formulas and settled on using a combination of Owns Corning insulation, 1/2" Dacron, and an outer cloth. The panels are 3.5 inches thick, and are 2' by 4'.

I would like to improve upon them, however the appearance is very good, and I would like to use the frame and outer covering again.

I have been hearing about the benefits of "rock wool", however this appears to be a term used in England quite often. I have found products referred to as rock wool in the US, but am unsure if its the same product. I also have considered placing an acoustic panel behind the cloth, which I suspect would act more as a diffuser than have any absorptive properties.

My concern with the current panels are that they attenuate signal at certain frequencies, but are not even across the mid to upper spectrum.

Any thoughts, observations, and recommendations would be appreciated.

Regards
Mister Pig

[bpape]

Simply changing the core material to mineral wool or rockwool isn't going to really change much - sorry.  However, if you are sitting close to a boundary like that, what you can do to improve them is to make them thicker to help deal with the boundary bass buildup.  You may find that it's really just bass boom changing and masking the tonal balance.

Bryan

[max190]

What Bryan said...plus I would add a panel or two above your listening position.

[richidoo]

I have tried adding a layer of palette wrap plastic over the absorbtion with good results. Also tried kraft paper. Both will get rid of the dry feeling of absorbtion. Kraft paper is more agressive in reflecting mid/upper frequencies. The thin plastic is less intense by reflective less mids. You can buy the plastic at office supply store, and kraft in small quantity at a crafts store. Put it as the last layer under the cloth covering. The cloth should be acoustically transparent like Guilford of Maine if you want to hear reflections through it.

I have also used small RPG BAD Panels very close behind the listening position (1-2 feet) with excellent results. Distance to these can be close.
Rich

[laserman]

+1 for what Brian and Steve said.

I used 4" thick OC703 and affixed them to a free standing wood screens 5 1/2' X 5' with about two inches of air space behind them.  This was a huge improvement in my room.  Pictures are in my gallery.

L