Ground hum????

[owen_vallis]

I know that this has been brought up before, but I can't find a solution yet. I built a 12 pair Mogami snake box for my drum room, but there is a hum in the signal. The box I built for my vocal booth is clean, but the drum room seems to pick up a hum from somewhere?? The wierd thing is that when I hold the mic and touch the box at the XLR input the hum disapears. I'm thinking of wraping a wire around all the female XLR inputs and then running that to a ground in the room. Let me know your thoughts.

 

[Rokket]

You will have to make sure that all your XLR connections are wired correctly. It sounds like you may have a ground not properly attached to the right post in one of your cables.

Here is a link:

http://www.recordingeq.com/EQ/req0400/cords.htm

It goes step by step on wiring XLR, TRS cables...

 

[owen_vallis]

All the grounds are wired to the correct posts. Maybe I didn't use enough soder? The connections are all stiff though.

 

[Rokket]

hmmm. It only happens in the drum room? And all your connections have been checked there? Did you check to make sure the shielding goes up as close to the connector as possible (no internal wires showing outside the XLR connector)?

Beyond that, I'm stumped...

 

[owen_vallis]

I figured out the problem. I used multiple point grounding for each Panel mount Female xlr and then ran the wire to an external ground wire. The noise is all gone.

 

[Rokket]

I figured out the problem. I used multiple point grounding for each Panel mount Female xlr and then ran the wire to an external ground wire. The noise is all gone.

Woohoo! I'm glad you found it. It never hurts to look it over again with a fresh perspective!