RCA connectors are commonly used to connect speaker wire to audio systems. RCA connectors carry a single audio signal. The signal is transmitted on the centre or positive pin, and the ground connects to the outer portion of the connector. Dual RCA plugs are most commonly found in red and white pairs. The red is the right channel and the white is the left. The second most common is red and black, with red as right channel and black as the left channel connection.
Using a tape measure and wire cutters, measure and cut the length of the speaker wire to be used as the speaker cable.
Separate the two leads about 2.5 cm (1 inch) long using a utility knife or your fingernails. Separating too much of the wire will result in the cable being apart above the finished plug. Strip about 1.3 cm (1/2 inch) from the end of the cables with wire strippers and twist the stranded wire together with your fingers.
Pull or unscrew the sleeve from the RCA plug and slide it over the cable. Be careful not to forget this step. If you forget, you will end up removing the newly soldered plug and connecting it again.
Examine the cable to determine which lead is positive and which is negative. Look for a variation in the pair of wires. The positive wire will have ribbing on the insulation, a marker stripe on the side of the lead, or a silver streak inside the conductor of the cable. If the cable is red and black, the red wire is positive and the black is the negative lead.
Connect the positive wire to the centre conductor of the plug. Using a soldering iron, hold the tip on the connection point and melt a small amount of solder on the wire until a solid connection has been established.
Connect the negative wire to the soldering tab connected to the side portion of the plug. Melt a small amount of solder connecting the wire to the tab.
Pull the plug sleeve up to the connector and push or screw the sleeve into place.
Repeat this process for all other connectors.