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House Wiring Defect?

Recently I introduced a new power amp connected to my preamp with XLR cables. The pre and power amps were plugged into different outlets in the same room which produced a pretty loud hum from both speakers with the preamp on or off and the power amp on. After the inital freak out and a check of all connections I realized one fix was to power the pre and power amps from the same outlet. This restored quiet operation using either outlet. The question is, does this indicate a house wiring defect or nothing to worry about?
rockvirgo

Showing 2 responses by soundoctor

soundoctor
7 posts
 
Please be aware that most "microphone" cables (i.e. from a "music store") are incorrectly wired -- they often have pin 1 tied to pin 0, which is the shell. As clever as this is for electrocuting musicians, we still have musicians so the premise isn't working well...

Seriously, you'll have to open both ends and determine if the wiring is 1==1, 2==2 and 3==3, with nothing else.

You also might try disconnecting EVERYTHING, then start from the sub and speakers BACKWARD, listening to each step.

And of course IF you have TV cable connected to anything then that's very probably your culprit.

Regards,
Barry
soundoctor
7 posts
 
Please be aware that most "microphone" cables (i.e. from a "music store" are incorrectly wired -- they often have pin 1 tied to pin 0, which is the shell. as good as this is for electrocuting musicians, we still have musicians so the premise isn't working well... Seriously, you'll have to open both ends and determine if the wirinfg is 1==1, 2==2 and 3==3 , with nothing else.

You also might try disconnecting EVERYTHING, then start fro thje sub and speakers BACKWARD, listening to each step.
And of course IF you have TV cable connected to anything then that's very probably your culprit.

Regards,
Barry
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