Additional, non printed, non electronic parts:
To reduce weight the headshell and all other components (except for the ears) were printed using LW-PLA (lightweight PLA). This pla foams up above a certain temperature, which reduces its density greatly. There is a tradeoff of course, because as the density reduces so does the strength. Although in my experience even at 50-60 % weight (compared to “solid” PLA) it's still pretty tough and flexible.
My typical post processing sequence for PLA prints is as follows. Keep in mind this is just what I do CURRENTLY, and this is an ever evolving process and I do not claim this to be the “best” or “correct” way to do it!
You may need to repeat one or more of these steps (especially during sanding) depending on the print, and how fine of a finish you'd like.
Print settings for LW-PLA I used (on modified CR-10S with a microswiss direct drive extruder):
Initially the ears were printed out of regular TPU with a very sparce infill. This resulted in very heavy (250 grams each) ears, which made wearing the head pretty much impossible (very uncomfortable, too much inertia, and stress on neck).
For the final version, they have been printed using LW-TPU, without any infill, with 2-3 outlines (need to check). They then recieved a grey primer (Vallejo, 2 layers) and then were painted black(using Vallejo air black, again 2-3 layers). Finally they recieved 2-3 layers of glossy varnish. I used an airbrush for all of the paint layers. This resulted in ears that are under 100 grams each, which made a huge difference in comfort.
Printing LW-TPU can be a bit tricky as I learned. It has to be printed very slowly, and it sticks to the build plate extremely strongly, so it has to be removed carefully.
Print settings (on direct drive CR-10S):