Treehaus speakers.....! *LOL*
Never thought of using the live edge locust slabs I've got laying about here...
We typically make benches with them. Rubina is very heavy, and laughs at carbide bits, saw blades....even chain saws....
Subject to checking...but it's a thought.....
"Thermionic tubes".....? *G* Sounds like Formula E tech to me.... ;)