Compliant tube based headphone pad idea I had while riding a bicycle two days ago. I got the thickness and dimensions dialed for printing and bending, but I either need to setup my old KP3 kingroon with a longer 2040 Z extrusion or print this in 2 pieces. Either way, the joint connection needs more than just the overlap and glue. TPE would probably be better too, although I have no idea what shore hardness this $10 clearance spool of TPU has. The sound quality seems a little tinny and I have no way to tell how loud it is externally, but it is just my first iteration that I can put around my ear and test. TPU is so slow to print and the moisture levels impact the qualities drastically. I actually like the texture and properties of wet TPU more than dry, but it is hard to get it just right. With the design’s compliant bend, consistency is kinda important. Anyways, just another boring project. On the bright side, this seems cooler temperature wise when the TPU pad is against my ear.

I spent all day chasing custom logarithmic infill patterns that might incorporate a compliant bend but only learned about how not to do a thing like that in CAD.

  • @IMALlamaEnglish
    2•1 day ago

    I share your curiosity, but I don’t have a ton of time to dig into this right now beyond the thought experiment. That’s the reason for my slower responses :( Work is busy and the kids eat up most of free time.

    You’re right - the seal will directly impact bass. This is why the sound on some headphones will change fairly dramatically as you move your head around - you’re breaking the seal. For me, the head position most likely to break the seal is turning my neck fully in one direction and looking up, but it can also happen with less extreme head motions depending on the cans. I could see volume also playing a role, since the air volume inside the pad is effectively a resonator and changes in air volume will impact how it resonates. I suspect the material of the cup itself will also play a role. Something dense/reflective, like leather, will likely sound somewhat different than say a suede or a microfiber. That was one reason why I was considering gyroid - it would be reasonably non-reflective.

    After measuring my ear and looking at the CAD and print, my first prototype adds enough fore to aft clearance around my ear. It added around 3mm of extra depth. This clears my ear depth by about 1.7mm too far and is primarily from designing in a stiffer material than the original pad. The original pad touches my ear in several places which gets hot and annoying, especially in the summer.

    Sounds like a similar motivator to my “I wish these didn’t press on my glasses frames so hard” ;)

    A pop-tube seems like it would be hard to print vertically oriented. I suspect it would move around some as you’re printing thanks to not being very rigid. It wouldn’t hurt to try it. Printing it sliced down the center and laying across the bed horizontally seems like it would be easier. I certainly hear you on the joys of TPU stringing, but if it’s limited to the far ends of the print it shouldn’t be too horrible to clean up. You could even design it a touch too long and cut the ends off.

    Anyways, if I introduce this disconnected level of complexity to my next iteration, I can likely also add something like a recess for glasses too. I have the same issue with my reading glasses and just use ear buds instead when I need them.

    Depending on the spacing of the tube crinkles, you might be able to line them up so your frames fit between them. You could also probably make one crinkle stick out a little less and line that up with your frames.

    not that you should wait or anything like that.

    At this point, I have nothing but time. I’m also trying out a pair of ‘real’ ANC headphones, vs my office drone headset that happens to have defeatable ANC. They have ridiculously sized pads and they’re actually pretty comfortable with glasses. I am somewhat tempted to type out a mini-review somewhere here, but have no idea where I would post it.