3D printed in-ceiling Dolby Atmos Overhead Speakers?

I've printed my waveguide using a gyroid infill and filling them with epoxy. It is a good fill in that it doesn't trap air pockets. If I were to do it over again, I would spray the print with flexseal, then fill with water to make sure it is watertight, empty it and dry (obviously), then fill with epoxy. If you don't water test it - well, you'll find out why it is important. 🙂 However, the plaster of pairs seems like a good idea. perhaps put it on a vibration table or shaker of some sort to make sure it gets in all the nooks and crannies.

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Getting closer.... I've printed out a test enclosure and filled with Plaster of Paris mixed with wood glue. I'm going to print out the same test enclosure with 40% (grid?) infill and test both. Waiting on filament to be delivered...

I'm starting with the factory recommended crossover. Question for you guys with experience playing with passive crossovers... does this layout work? Suggestions for better layout? Thanks in advance.

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The two coils on the left are sub-optimally positioned, but you see placement like that in some commercial crossovers also, so it's not the end of the world. I think laying down the large coil and standing up the smaller coils might be better. Hacking this together with the images from Troels' site, something like this orientation:

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Generally, maximizing the distance between the coils is considered a good idea also. If you can move your capacitors and resistors toward the center and increase the coil spacing, that should help a bit.

http://www.troelsgravesen.dk/coils.htm
"The general rule of thumb is that we should not be able to see one coil through the center hole of another."

. . .

"Coils in midrange and tweeter circuits may carry very little current and can be placed relatively close, where a huge coil for bass may need more distance."

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