Continuing on from yesterday's TTOTD, we will now discuss wiring of XLR to TRS cables. (Please go back and read the TTOTD from 12/23/99 and yesterday's (1/4/00) to make sure you are up to speed on what we are discussing and why.)

Here is what we say is "normal" wiring for an XLR - TRS cable:

XLR End (male or female)	TRS End
Pin 1 - Shield...................	Sleeve - Shield
Pin 2 - Hot (positive)..........	Tip - Hot (positive)
Pin 3 - Cold (negative)........	Ring - Cold (negative)

Tip is ALWAYS positive in balanced TRS connections. I've never seen any equipment wired any other way as far as TRS goes. If you are interfacing a device using XLR connectors that is Pin 3 hot to a TRS device you will need to reverse the polarity of the cable as shown below.

XLR End (male or female)	TRS End
Pin 1 - Shield...................	Sleeve - Shield
Pin 3 - Hot (positive)..........	Tip - Hot (positive)
Pin 2 - Cold (negative)........	Ring - Cold (negative)

You can actually reverse the wire at either the XLR or TRS end, but the XLR end is usually easier. Again, don't reverse both ends or you will be back to normal. If you are connecting Pin 3 Hot gear to a patch bay that is otherwise all wired as normal just reverse the polarity on the cables running between the patch bay and the Pin 3 device. Again, you can do it at either end, but not both. Pick a standard way you will do this and live by it so you never get confused.