Stereo Headphones are generally supplied prewired with a 1/4" stereo jack. This plugs into the headphone output on audio equipment. Smaller headphones, such as those used for MP3 players use the 3.5mm mini jack.The jack plug can get damaged through general usage and need to be replaced. Stereo Jacks of either size have the same connections. They seperate the part of the jack that plugs into the socket into three parts; Tip, Ring and Sleeve. Each of these must be connected to the correct wire in order for the headphones to work correctly. However rewiring the 3.5mm jacks is more challenging because of their small size.
Cut the damaged jack plug from the headphone cable. Unscrew the shell of the replacement jack plug and slide it over the cable.
Strip back the outer sheath of the cable carefully, using the wire strippers.Then strip back the sheath around the wires from each headphone. Identify which are the left and right headphone cables.
Twist together the copper strands that form the screen, each headphone wire has one. The screen acts as a shield against interference so it is important that both are connected. Place a small amount of solder on the end of each wire and the screen by holding the solder against it, then heating the wire until the solder runs onto it.
Place the jack in the vice by the tip, making sure the terminals are easily accessible. Place a small amount of solder onto each terminal by placing the solder against it and heating it with the soldering iron. Keep each terminal separate from the other.
Place each wire against its respective terminal, then heat the wire and the receptacle until the solder flows together and the connection is made. Make the connections as follows: Left headphone wire - Center terminal (Tip), Right headphone wire - Small tab (Ring) and the Screen wires to the long tab (Sleeve). Once the solder has cooled, screw the jack plug back together.
Use a damp piece of cloth or sponge to clean the tip of your soldering iron between uses. This ensures good solder connections.
The solder should be shiny after it has been heated. This indicates a good connection. If it is dull ( a dry solder) then start again, making sure the tip of the soldering iron is clean.