Repairing 70's Headphones

I know I said I would do this next week, but as the hard drive that i've been waiting for to fix up a laptop didn't come (grr!) I had pent-up geekery to expend. So, you all get to learn how I went about fixing my Rotel headphones, with the able assistance of my room-mate David.

First of all, I required some equipment;

• a carpet cutter
• a wire stripper
• a soldering iron
• electrical solder
• a new jack (I chose a gold 6.3mm one, but I could just have easily converted it to a smaller size for an Ipod or whatnot. I'm a dork, so I prefer to use an adapter.)
• a cardboard mat or other safe surface to play on.

Step one:
obviously, the old jack had to go. after I snipped that off with some wire cutters, I had to expose the wires. This was a little fiddly, as the cord was too thick for the sort of wire strippers with which you put the cord in and then press and pull. Instead, I cut around the wire in small bites, as illustrated:The wires, as shown, were red, white, and black, which correspond to right headphone, left headphone and both, respectively. This was discovered after some thorough googling, and finding the general consensus. some set ups have enamel coating but unfortunately mine were covered in plastic sheaths which needed to be stripped:


Step Two:
I found the best way to strip the wires was with a carpet cutter and a steady hand, scraping the plastic off much the same way you would whittle a pencil with a knife. The wire strippers I had (see in the above photo) were sharp and pulled the wire out with the plastic sheath.

Step Two And A Bit:
Now is a great time to put on the screw on end-y bit (technical term) that was in the upper left hand corner of the first photo, onto the cord. This means when you solder the wires to the jack, you don't have the protective cover for the wires left over - I did this and had to remove the wires and re-solder it and my second job wasn't as good as the first. I didn't have any solder remover, so you may want to buy that too if you expect to make a buff job of it.

I found out which wire connects to which terminal, though the wires were different colours to mine in his blog. In case his site goes down, i'll repost the relevant quote:

"

1. The “Tip” (the end of the connector), which handles the left stereo channel. For me this was the blue wire, which I connected to the shortest terminal.
2. The “Ring” (the first segment of the connector), which handles the right stereo channel. This was the red wire, which I connected to the middle terminal.
3. The “Sleeve” (the second segment of the connector), which is the common ground. For my headphones, this was the conductor with no insulation on it. This was the wire with no insulation, and it connected to the ground terminal.
   

"

Apparently he got that more or less from Wikipedia.

I also found this picture helpful:


Step Three:
When soldering, you'll want to have something to hold the jack and cord in place while you wield the soldering iron and solder. I was fortunate to have a second pair of hands in the form of my room-mate, but if you're going to be touching the jack by hand, make sure not to handle it directly as it will get very hot. I used my adaptor which has a plastic covering to let David move it as I went to each terminal - but you could also use whatever it's to be plugged into to hold it there as long as it's turned off. Just don't touch the turntable or whatever with your soldering iron!


Step Four:
My jack came with the plastic cover above, but unfortunately it was lost. I used epoxy to insulate the wires instead, which does much the same thing with the added advantage of being very strong if the plug was pulled.


As you can see, I made a dog's breakfast of it, but fortunately this was mostly hidden by the metal covering and coil. I recommend you do both this and the soldering in a bright, well ventilated area.

And that was it! You should probably wait for the epoxy to set before screwing in the cover, but I just put it straight on as it was dripping off the jack and I don't plan on soldering through epoxy anyway.


Awesome. I would like to thank Chris Metcalf, whom was the primary source for most of this knowledge.