It's frustrating when a perfectly good pair of headphones has to be retired due to a damaged cable.
I have found myself in that situation once too often, when the cable in my trusty Beyerdynamics has once again failed.

So I decided to seek for a way to make the problem go away for good: I decided to mod the cable into a RCA jack.

Why did I decide to use RCA? Many people recommended using obscure connectors to achieve balanced output, but I had no experience with that and my hardware didn't support it.

So, I ultimately decided to stick with the tried-and-true RCA plug.

Disassembly was a simple process.
Just a matter of unscrewing couple of screws and pulling the "shell" apart, to be precise.

The cable itself is a simple 3-wire cable, that goes from one ear to the other over a headband.

As I have decided to use RCA plugs, which are mono traditionally, I didn't need the wire going over from one ear to the other, so I cut it off.

instead I widened a hole in the shell where old cable was, and soldered the RCA plug in place.

On the other side I have guesstimated the bottom of the shell, and just made a matching hole for another RCA jack.

The process of modding the cables turned out to be easier than expected, with only one minor hitch along the way:
  The plug I chose was a bit too large, and wouldn't fit in the speaker with it in place.

The solution however was simple, because it torqued pretty well into the shell, and very obviously had more than enough leverage on the nut, I decided to use the Dremel and chip away some of the metal on the nut, after which it all fit wonderfully.

It was a quick and easy fix that allowed me not only to restore my headphones to full functionality, but also breathe new life into them.
No more adapters necessary when switching between my PC's 6.3mm jack and my portable player's 3.5mm jack.

These Beyerdynamics are back in daily rotation, and it's all thanks to a simple cable mod.

P.S Not showing the soldering, nothing glorious to see there, sorry.