Building Balanced XLR Cables

I am building XLR cables using 3 conductor + shield wire. Typically I would solder the shield to ground, 1 wire to hot, and 1 wire to cold. Should I connect the 3rd wire to the ground (shield), use the 3rd wire as the ground (not use the shield at all), or not use the 3rd wire at all? Thanks in advance.  

Showing 3 responses by auxinput

ah, just re-read your first post.  If you have a braided wire shield, I would solder that to the "shield" connection on the source XLR plug (typically a female plug).  If you have a "floating" braided shield, it tends to create capacitance and reduces high frequency response in the cable.
I would take b4icu's suggestion with a grain of salt.  It may be true in some specific circuits, but not all.  See this guide:

The shield connection on the XLR is basically connected to chassis/ground.  This may be completely different than pin 1 "signal ground".  If you have a cable that has 2 conductors and a braided/foil shield, you can connect the shield to "pin 1".  This is common shared signal ground and may be required in some audio circuits.

That being said, I have have had great success in making cables that use three 20awg solid-core conductors in a braided configuration for pins 1, 2, 3.  I don't connect anything to XLR shield/chassis.  This is very similar to how Kimber Cable makes their interconnects (but they use stranded conductors).
The 4th wire is not for powered microphones.  Powered microphones use what is called "Phantom power".  This is DC voltage that is applied to the signal wires (pins 2 and 3).

The 4th connection on the XLR plug is connected to the equipment chassis/ground.  This can actually be different than Pin 1 signal ground (which is a common/shared ground for the analog circuits), but not necessarily a different connection on all equipment.