Something relatively new in sound absorption...

[P.I.]

Cotton eggcrate panels:

https://www.acousticalsurfaces.com/echo_eliminator/studio-wall-panel.htm

Better performance than foams and friendlier in many ways!  I'll be using it in my new speaker build.

[Nick B]

What an environmentally friendly product. Pls post your impressions whenever you get to that project 

[S Clark]

This looks really interesting.  How expensive is it?

[HAL]

Dave,
Thanks for the tip.

Just talked to them and they no longer make the eggcrate style panels.  Only have the flat panels in a lot of colors. 

The acoustical properties are the same for both styles.

Might be a good replacement for all my old and deteriorating Sonex Foam.

[P.I.]

This looks really interesting.  How expensive is it?

Even tough I'm not an Amazon fan:
https://www.amazon.com/Echo-Eliminator-x24-Density-Black/dp/B00RLVTTVM

[S Clark]

Thanks Dave.  Looks about the same price as Danny's No-Rez.  I was hoping it would be a cheaper option. 

[tmazz]

Maybe in the other house where I had a dedicated listening space in the basement, but now that my system resides in the living room it would take about five seconds for me to get if I ever tried to put that stuff up.   

[Nick B]

Maybe in the other house where I had a dedicated listening space in the basement, but now that my system resides in the living room it would take about five seconds for me to get if I ever tried to put that stuff up.   

Hmmm, additional confirmation of your wisdom 

[HAL]

No problem.  Wrap it in Gilford cloth and it looks good.