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Ground Isolation, removing sibelance.

Hello all,

Is there some 'safe' way to isolate service grounds, or cable TV grounding apparatus to overcome the unbearable attributes they can induce into a system?

biteing the bullet and having Verizon FIOS completely installed just today I've noticed once agin the bug a boo of induced sibilance raising it's ugly head in my music system. I'm almost positive the FIOS is the culprit... albeit the 'grounding' of it. I did already disconnect the 'battery back up' for the phone service portion... yet today after the install was complete and after several hours the 'ground loop' induced sibilence was definitely apparent.

As an all underground fiber optic network, my first thought was to simply disconnect their ground wire from the service pole ground. I just don't feel too good about going in that direction... especially if I can 'isolate' it electrically somehow and maintain circuit integrity and safety.

Anyone know who, what, and where, to remedy this issue?

thank you very much.
blindjim
mcfarland
356 posts
 
Mondial "Magic" ground isoation device. About $75.
blindjim OP
3,092 posts
 
Mcfarland, thank you very much... I'll look for one of those gizmos if in fact I find the 'cable TV' the culprit, as I do highly suspect it to be... gotta disconnect it entirely first.

As the foremost symptom of ground loop issues is 'hum', or that offensive 60 cycle 'buzz' at the speakers, I'm not realizing that aspect. Simply sibilance. No hum or buzz. Fuzziness in the upper mid to treble ranges... most noticeable in female vocals and somewhat in the brass section, and then only from time to time... not constatly apparent. (if it is constant, I'm detecting it only at some frequencies then)

As much of my system is balanced though, not all, perhaps this is offsetting a good portion of the 60 cycle buzz, normally associated with ground loops.

I mainly suspect (if it's not the cable TV), it may be 'digital DC leakage' finding it's way back into the system. I'm gonna start the unplugging and flipping breakers today.

I did also run across the link below by doing a 'Google' search for "cable tv hum". The info provided therein is quite extensive and easily understood... with several possibilities outlined and a method for ascertaining just where the problem is or may be.

http://www.audioholics.com/techtips/setup/avhardware/groundloopcableTV.php

Probably not the last word on things but quite thorough and beneficial.

A quality iso transformer integrated in at either the service panel, or breaker box would be my prefference. As it covers a far wider approach... isolating the 'cable TV' ground, an additive measure of far less cost is also my pick. Between the two items things ought to shape up.

I'll follow up with my findings.
bbaxley2
141 posts
 
look at parts express they have a little black on for cable hum and its under 10.00 and works
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