The idea that’s swimming around in my head is to make a mic set up like V-MODA boom mic, but will work with any pair of headphones you have, and I know that the mod mic is a thing, but I’m trying to go for a single cable solution. Is there a reason that this isn’t a thing that’ll work, are there any suggested parts, has someone done this before and I’ve just missed it?
You would need a 4-conductor + Ground cable for this. LiYCY-type cable should work for this.
And even then, crosstalk from the headphone-out to the mic-in may be an issue.
The “easy” part is the mechanical side of this.
Electret mic-capsule, arm (carbon fiber tube?) and some connector parts (bent metal, wood, 3D-print, etc.).
The difficult part is to do with the electronics as you need to avoid passing the bias-voltage from the microphone jack to the signal outs on the headphone jack.
AFAIK, Mic-jack pinout is like this:
| Pin | Function | Note |
|---|---|---|
| Tip | Signal | from microphone |
| Ring | Bias Voltage | to microphone |
| Sleeve | Ground | Or shield, not super sure about its role in this |
Headphone jack pinout:
| Pin | Function | Note |
|---|---|---|
| Tip | Left | |
| Ring | Right | |
| Sleeve | Ground |
Concerning circuit setup, I would just point you at this thread on L1T:
The alteration in your case is that you don’t have an external mic-preamp, so no need to do any Op-Amp related shenanigans.
headphones have quite a few different connections. in order to make a universal, you would need the end to accept a lot of different connections that could be swapped out. something along the lines of what hart audio cables does, but in reverse(he has an adapter on the amp side)
1 Like
The three common ones are 2.5mm, 3.5mm and miniXLR.
Easiest way would be to have a 3.5mm TRS socket and using short adapter cables.
Question then is how to mount the device to a headphone.
vmoda boom mic style, have the mic come off of the cord. shrink wrap + electrical tape will make anything very stiff.
edit: or resin coated
edit2: shrink wrap + resin coat would most likely eliminate cross talk as well.
The best way is to have a shield on the aggressor conductor, or a ground-trace between signals.
1 Like