Guide: How to Make a High-Quality Audio Interconnect for Your PChardnrg - May 29, 2007
Making The Interconnect - 3.5mm Jack Plug End:
You'll have to smooth the sleeving over the cable from tail to head to get it to go over properly all the way. After a while you'll get the sleeving over the cable. Leave a bit hanging over the tail end and pinch it down to put the connector barrel over the sleeving and cable, push the connector down along the cable and then work the sleeving down to expose then end of the cable.
Cut the sheath of the cable, taking care not to cut the shield. I find it easiest to use a sharp knife and cut around the sheath and bend the cable to split it at the cut. So I don't actually cut all the way down to the shield.
Make sure you remember to place the insulating tubing over the cable if you are using a metal barreled connector
Size up the signal cores against the connector and trim them down to line up with the terminals. I used blue for left and red for right. On a 3.5mm connector, the centre terminal corresponds to the tip of the jack plug, which is the left channel. The middle terminal corresponds to the ring or middle section of the jack plug, which is the right channel. The shield connects to the larger outer terminal.
Strip the signal core cables down, apply flux and tin them with a small amount of solder. Apply flux to and tin the shield wires too.
Line up the cable to the terminal and hold in place. This is something I can rarely do easily without the use of the crocodile clip stands. Then dab on some flux and apply heat to both the terminal and the core cable, and let the solder flow onto both. You should end up with something like this.
Do the same for the left channel (blue in this case) to the centre terminal. As you can see, I twisted the shield into two parts, this makes it easier to solder than one big twisted shield, trim it down to size, apply some flux to it and the shield terminal, and solder one near the edge of the inner side and one to the opposite edge
Inspect the solder joints to make sure they are solid and not cold-soldered. Use some pliers to clamp the cable down firmly, and then slide the insulating tubing up over the connector assembly.
Push the braided sleeving back up. You could wrap a couple tight turns of electrical tape around the sleeving to secure it in place at this point. I chose not to because the cable, sleeving and connector make a perfect snug fit (no coincidence since I chose them to allow this).
Time to take a quick break, get a refill and admire the first half of the job!