@Ricosound: For Warnex and I imagine similar protective coatings like truck bed liner, the short dry-time in combination with a structured roller (
sentosa.ro/wp/wp-content/uploads/Trafalet-T13.png), gives a thicker orange-peel like surface area.
thumbs.dreamstime.com/t/ruwe-oppervlakte...-warnex-30184373.jpg The uneven skin is much better in hiding scratches (which are inevitable after a couple months on the road). It's one of the few exceptions to the rule that multiple thin layers are better.
Plywood chipping away around cuts is in my experience is due to less then razor sharp saw blades. In those cases where the latter is unavailable, it can help to make a raw cut first, after which the final cut is made one or two millimetres smaller/ larger, at a slower pace.
@ROSSSSS224: If you make the horn larger and thus the chamber smaller you'll get some extra efficiency overall in return for a higher f3. Making the horn larger around the area you describe, would increase efficiency in the 63 Hz area. So altogether a more 63 Hz experience, in return for slightly less low frequency response.
If your costumers start reporting a negative detail to the sound, which they mention to be a "je ne sais quoi", you might be in the know of what that actually might be. Until then using more "correctly build" Cubo 15's will even the effect out.........eventually.
Just build (loads) more Cubo's
Best regards
Cubo