Richlite is a man-made material almost as dense and heavy as granite and naturally non-resonant. Richlite is available in thicknesses from ¼” (6mm) to 3” (75mm). Making the NX-Otica with 1-1/2" thick Richlite will challenge any builder but the sound would be stunning. The material can be cut and shaped using industrial grade woodworking tools with carbide saw blades and router bits.

I have played with Richlite for a few projects. Cutting 1-1/2" thick Richlite will require a 5 hp - 3 phase table saw with a new 12" 60-80 tooth triple chip blade and still it will be real slow going and slightly scary. Using a lesser table saw will trip your breaker. The wave guide can be routed in with a 3-1/4" hp router, I use a Porter Cable Model 7518, it's a beast and unfortunately no longer made.
Cut edges can be sanded and polished down to the micron level using a random orbit sander. An industrial air powered sander like 12,000 rpm
Dynabrade sander would be ideal, note that most hobby compressors will not put out the required 19 SCFM. The 1-1/4" Diameter Mini-Dynorbital Extreme would be ideal for sanding the wave guide and it only needs 5 SCFM.
Assembly is with biscuits for alignment and epoxy, fun stuff that gets everywhere.
Richlite has a sample pack with sizes and colors
Ready for a challenge?