@c76776cc messier if it breaks but could work too 🙂 dampening would be better than plaster i think… if the sand is fine enough and does not vibrate itself against the plastic shell. I could imagine that happening if the space between walls is not big enough to filter all resonances 

 @96f216d0 Yeah, that's right. However, enclosure walls are 1cm thick, I use 6 wall loops for inner and outer walls with quite enough infill. The material is the very stiff Bambu Lab PLA-CF.

So, we will see. 😃 

 @c76776cc the bad thing with speakers is always that it’s so subjective and cannot be conveyed over the internet how good or bad it really is. You’d almost always hear it yourself and then the personal preference kicks in 🙂 

 @96f216d0 Yap, but taht's okay. These are for me. 😃