Further to my first question about wiring the basement with in wall XLR cable to my mixer

Question

I bought and installed this cable in the walls about 4 months ago, and I am planning on using it for both the xlr and 1/4 inch jacks... https://www.primecables.ca/p-313998-cab-5978-all-80mm-professional-microphone-bulk-cable-3-lengths-available-monoprice#sku313998

So the question I have is for the guitar plug in... should I run the two wires to hot, and the shielding to the sleeve, or just one connector to hot and the shielding to sleeve???

Based on feedback from a member, I am going to dedicate one cable to one plug in for the xlr and a separate cable to the plug in for the 1/4 in and have them always plugged into the mixer.

The longest guitar run is 20 feet across the room, (plus up and down inside the wall) so I am looking at a cable length of not more than 36 feet. All the other runs are shorter, and the shortest one is maybe 14 feet. Then I have the length of cable from the instrument or mic to the wall. I have a few 10 foot XLR and 1/4 inch cables for that. Your thoughts before I wire that jack up and try it?

Our lead guitar player uses an amp, but the rest of us are Guitar, keyboard, and mandolin so we use the 1/4 inch connector to the mixer. Everyone uses a Shure 58 Microphone.

Any thoughts would be appreciated Thanks

Answer 1

When using this setup I would connect as this:

• At "guitar" end: tip to one wire (often the red one), sleeve to the other wire (often white). No connection for the shield, but see below.
• At "mixer" end: connect tip (red) and sleeve (white) as before. Connect shield to common signal ground used for all the shielded cables.

In this way the shield "protects" the signals from outside interference but does not transfer signal here.

It is slightly different for the XLR as there the shield will transfer "signal", albeit only the return for the 48V phantom power if you use that.

I would connect the metal box holding the XLR and guitar inputs to exactly one of the shields in order to not get a ground loop.

You need to test this first, as sending guitar level signals over long cables can be very tricky. It might be better to get a DI box with a transformer solution at the guitar end and send the signal into your mixer instead. The player could then have a very small amp, say a Vox 15, for hearing himself playing. Put a mic on that amp as well so you get both a clean and a miced signal into the mixer.