The XLR audio connector is widely used in consumer and professional sound reinforcement and recording equipment for its durability and functionality in balanced audio wiring applications. Save time and money by using your basic soldering skills to wire your own XLR adaptors when you need to connect multiple components using these connectors.
Strip ¾ inch of the outer insulation from each end of the shielded cables. Unravel the exposed woven shield braid at each end of the shielded cables, and twist it into a single conductor. Strip ¼ inch of the outer insulation from the ends of the two inner wires at each end of the shielded cables.
Use the needle-nose pliers to twist the bare ends of the same colour inner wires together at one end of each shielded cable. Twist the shield braid conductors together. Tin each of the joined inner wires and shield braid conductors with the solder. Tin the bare ends of the inner wires and shield braid conductors at the other ends of the shielded cables with the solder.
Remove the XLR plug head assemblies from their barrels. Either rotate the barrel sections counterclockwise to unscrew them, if they're the Neutrik type, or unscrew the small slotted screws securing the plug heads to their barrels and pull them apart, if they're Amphenol types. Looking at the front of the XLR connectors, top left is pin 2 (nearest the raised key ridge on the body of the plug). Top right is pin 1 and the bottom (middle) one is pin 3.
Solder the joined pair of twisted shield braid conductors to pin 1 of the male or female XLR connector. Solder the joined pair of the dark (red or black) inner wires to pin 2 of this XLR connector. Solder the joined pair of the white inner wires to pin 3 of this XLR connector. Examine the soldered connections carefully for and shorts or bad solder joints. Slide the barrel of this connector over both shielded cables and reassemble it.
Slide each of the other XLR barrel assemblies over the shielded cables. Solder the shield braid conductor and each colour inner wire to their respective pins on the other two XLR connectors, as noted in Step 4.
Examine the soldered connections carefully at each connector for shorts or bad solder joints. Reassemble the XLR connectors. Connect the adaptor to the components to check its operation. Disassemble the connectors, and recheck the soldered connections if a problem is noted.
Use the minimum length of cable possible for the adaptor to minimise hum pickup and noise interference.
Lower the sound-system volume when plugging or unplugging cables to avoid any speaker or hearing damage.