That's where these guys for I'm SYOS are good. They worked on the geometry vs sound output. The obvious tech is 3D printing, but I think a but if hand finish wouldn't hurt. By a qualified mouthpiece expert of course...Are they sending them out straight off the printer? I'd assumed they would need hand work on the facing.
Does anyone know what 3d printing technology they are using?
I have made a mouthpiece on an LCD resin printer. I designed it in Fusion 360 and although it's playable it sounds awful and plays about a quarter tone flat. The internal dimensions are very approximate so that wasn't unexpected and I consider it a successful proof of concept. I think the internal volume is too great and the baffle is a bad shape. I did do some light sanding of the table and rails just to remove the layering artifacts (0.05mm layers). I doubt I'll take it any further. I don't have suitable tools to measure the inside of an existing mouthpiece accurately (and don't even know what they would be) and my CAD skills aren't really up to translating such measurements into a 3d model.
I wasn't expecting smudges, smears of blurs as you'd find on casted products.