Quadratic Diffusers

Rix,
Absolutely at some point I will experiment with more diffusion behind the speakers. I like this "effect" better than absorption. 

As far as moving forward... I've been experimenting with diffusion in the room corners lately. That being... Taking 8' long 3" I.D. cardboard tubes (I get bar stock shipped in these types of tubes) and drilling approx. 125, 5/8" holes in them (somewhat equally spaced all the way around/top to bottom), then covering them with with plastic mesh material & capping top & bottom. This has also helped with overall system clarity, although to a lesser degree than the wall-type diffusion panels.  

@boxer12 - an interesting idea, one I'd never come across.
It kind of sounds similar to a Binary Amplitude Diffusor BAD?

Has anyone reading this come across a folded well diffuser? Tried them?

absorption and diffusion are two faces of one entity called 'acoustic optimisation'.

their mutual balance totally determines correct presentation of highly valued musical criteria for reproduction quality:
spatiousness, presence, focus, ambiance, directness, convincing power, non-coloration and dynamic contrast
- Source ReadScaped DIY QRD Diffusers

Rix,
Thanks for the quote above. Makes good sense.

IRT BAD, it looks like they are using absorption in those. The ones I've made are hollow & capped top & bottom. I did try these with wool balls inside them & liked it better (in my room) without.   

@boxer12- can you send me a link of an image or page with IRT BAD please?

https://kedap-suara.com/wp-content/uploads/2020/01/panel-akustik-bad-diffuser.jpeg