Report TA3 Problem in Do It Yourself Posted September 17, 2012 You have to fill the cups with solder so when you insert the tinned wire you get a good connection with the cup solder covering the wire. If you can see the strands of wire in the cup on the finished connection there's not enough solder in the cup and the solder should be shiney. If it looks dull there's a cold solder joint in the making. Using .032 diameter solder is my preferred size for all audio connectors Well, we differ on technique, but the result is the same. I still like doing it my way better, go figure.