So part of the COVID lockdown craziness is that we adopted some kittens that were literally born in the bushes outside our house. They've been great to have around, but they do like to chew through things, which most recently included the headphone cable of my nice Grado Labs headphones.

After way, way too much research, I've found a guy who makes a really nifty kit that lets you convert them to replaceable headphone cords. He also makes really nice wool replacements for the earpads. https://www.beautifulaudio.biz/

If you look specifically at his 3D-printed cable adapter, there's room in there for just about any sort of small connector. He's doing a 3.5mm phono jack. But, again after way, way too much research, there seems to be something of an emerging standard around MMCX connectors. These are the standard for high-end in-ear monitors, and if you go with them, you can buy all sorts of clever accessories, including cables with built-in microphones, Bluetooth adapters, and so forth. So I definitely want to do MMCX.

So here's where it gets tricky. I need to source the right connectors. I *believe* that I want something that looks like one of these:

https://www.amazon.com/Acxico-Female-Solder-Connector-Adapter/dp/B083XBCW5D/
https://www.amazon.com/KOOBOOK-Copper-Headset-Earphone-Connector/dp/B07WCNG54F/

I'm a bit put off by their wildly unspecific shipping date, on the first link, and these are, of course, no-name vendors, which spooks me a bit. Okay, so what about DigiKey? Here, I'm running up against my ignorance of the proper vocabulary for searching up these parts. They appear to carry 130 connectors, any of which might be right. I've gone through all the "free hanging" and "panel mount" jacks, and none of them seem to have two simple solder terminals and I'm done. They're all much more complicated. And everything that's left seems meant to mount on a PC board, with chunky alignment pins and a central wire that you'd solder to a through-hole or surface pad.

Example complicated connector: https://www.digikey.bg/product-detail/en/w%C3%BCrth-elektronik/66026421110620/732-14228-ND/10281428
This one is typical in having some sort of "ferrule" that you need to crimp onto the signal wire, and seems meant to connect to a coax cable of some sort. I don't think this is easily finessed into dealing with the two bare leads that I'll have coming out of my headphones.

So, am I missing something? What's a reasonable vendor who can sell me the right sort of connector, with a reasonable expectation of it showing up on my doorstep in a reasonable amount of time?

Indeed, I just got a pair of Mackie in-ear monitor headphones that use MMCX connectors. You can swap out the headphone cord for a bluetooth adapter and mic, using that connector, for instance.

I don't have an answer to your question at the moment. However if I were in your shoes, with that particular pair of headphones, I'd stick with the 3.5mm adapter as designed.

Reasons:
- I find the MMCX connector to be very fiddly to use. I have trouble plugging them in and knowing if they've snapped in properly or if I need to still apply more force to get them in. I'm always afraid to break them.
- If I needed something with an inline mic, I'd just swap to that kind of headset. (On those Mackies I just got, I played with the BT+Mic adapter and the latency delay is just too much for me to make use of it.)
- 1/8" cords are easier and cheaper to find and source than MMCX cords. Especially if you've got new toothy kittens.

Apparently, Monoprice's fancy Monolith headphones used to use MMCX and switched to 2.5mm jacks, specifically because people found MMCX to be too fiddly. So now I'm thinking 2.5mm.

Googling for "mmcx fiddly" found me this deja vu thread: https://www.reddit.com/r/headphonemods/comments/govjc0/mmcx_connectors/