kisslicertalk.com

The "trees" against the windows were printed on an Ultimaker 2 using KS, taking about 3 months and 18kg of PLA. Each square pocket allows a unique amount of light transmitted, giving colors ranging from ivory to taupe during daylight (at night they are white). The depth of the square pockets is up to 6" deep, and the effect is to diffuse the sonic reflection from the back of my flat-panel speakers, giving a less-distorted and more natural acoustic stage.

Cool

Ya, that is cool for sure. And costly in time and money. Lacking experience in acoustics I would not thought to build this. Does it work well?

It works nicely to remove inappropriate reflections off the back wall. It improves high-end clarity considerably. Google "acoustic diffusers" - they are commonly used in recording studios.