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Jl audio fathom f212v2 noise and hum

Just picked up a pair of these to replace the svs pb1000 i had prior. However after plugging these in to the same outlet (its a panamaz suge protected outlet) i’m experiencing two things i did not experience with the svs pair.  1) there is constant low level noise, like a very low white noise that is present when on, even if not connected to anything else. 2) a cyclical hum that seems to come on when my panasoni vt60 plasma is on. I beleive these are likey using the same circuit/ are wired though on different outlets.

Ive tried rca and balanced cables. No discernable difference there.  The subs are massive to move but next step is im goint to try them on dedicated circuits in a different room to see if that does anything.  Open to ideas here and hoping there is a solution. Thanks! 
esthlos13
esthlos13 OP
90 posts
 
Cable tv ground loop eliminator and emotiva cmx-2 have been ordered will post back in the next week or two when they have been tested. 
esthlos13 OP
90 posts
 
So I received the CATV ground loop eliminator - that seems to have taken care of the cyclical hum I was hearing.  However when bright scenes show up in the plasma or I’m fast forwarding there is still hum that seems to track with it. Hopefully the Cmx-2 will help with this. 
esthlos13 OP
90 posts
 
Emotive finally restocked the CMX-2, and I got one. And that did the trick for the hum

only question left is whether all jl audio subs have a small pop when turning on.  It’s  not loud but loud enough to hear. Hoping that’s normal.....
wloeb
43 posts
 
Is the sound coming from the speaker cones or from the transformers in the plate amp?  If it's transformer hum it comes from DC on the AC power caused by load imbalance.  Plasma TVs and light dimmers can cause this.  If its not coming from the speaker cones, it's not a ground loop.

This product solved the same problem for me:

https://avahifi.com/products/humdinger-dc-line-blocker

the Emotive CMX-2 should also work.
esthlos13 OP
90 posts
 
Hi wloeb- I’ve been able to fix the hum issues through the use of the emotiva CMX-2 and a filter I inserted into the coax cable prior to the connection to the TiVo mini

The one residual question I have is around subwoofer thump/ when they first turn on. I have them in standby so as soon as a signal is recognized they turn on, however there as an audible thump. 
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