Experiment question about sound treatment project

@hilde45 I purchased a large thick woolen rug from an estate sale.
As I work in the Texan oilfields I often build racks using double uni-strut.
This along with spring nuts and some L and T shaped plates bolted up nicely to make a frame which I draped the heavy rug over.

On the frame there is a five inch gap between the front layer, and the rear layer, and then a three inch gap from the rear layer to the wall.
Sound has to pass through two layers before it bounces off the wall and back through the two layers to get back to me.

I am building four QRD17 quadratic diffusers, two will go on the inside of the frame held about three inches above the floor (under them will be cabling etc tucked away, with generous arcs to allow air between them and suspension system to elevate cabling). And another two QRD17 outside to play with positioning.

Wool, believe it or not, with air gaps and layering is surprisingly good. The distance away from the wall made a difference. To give some idea of scale, there's 8.5 feet between tweeters on my stand mount speakers (last photo).

https://systems.audiogon.com/systems/8721

@rix Nice photos and system. Interesting solution. Question: does the frame vibrate and does the fact that the rug doesn't go all the way behind each speaker matter?

Hmm, I would imagine that the frame material in rixthetricks system would cost as much as several finished panels from acoustimac which I have used in my room.

@goose Agreed, but he seems to have access to materials. I am not going to do things that way but it's interesting to see the concept he's deploying.