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Advice on RFI with a new integrated amp

I need some assistance on my Exposure 2010S. The only input I am using is the cd player, but with volume turned all the way down, I am picking up radio signals. If I turn the dial to the moving coil phono setting, even though nothing is attached to it, I can hear radio pretty loudly.

The corner of the house where our stereo is in under the outside wires, and it sits right next to the terminal for our Verizon Fios -- not the most ideal location, but it
is the only option.

Using the CD pots on the amplifier, you can only hear the radio pretty faintly, when the volume pot is turned all the way down. If I am playing cds, you can't hear anything, but since when I switch to the phono/aux1 setting, as I mentioned, I am picking up radio signals, and
the volume is louder. From what I read (and hear), it appears that the phono pot (perhaps in cahoots with the moving coil phono stage) is acting as a antenna, and picking up signals, which are cross-talking
across the other inputs on the amp.

How would you recommend addressing this? I am currently considering
shorting terminators on the phono, and other output pots and found some terminators online (audiophilia article).

At first I thought it might be my changing the speaker cables, from very thick cables to the slimmer DMNs, but that would not explain why the RFI is louder at the phono input than any of the others.

Whatcha think? Does this make sense?

The other option would be RCA caps.

Thanks,

Marty
martyw
martyw OP
68 posts
 
Hi Al,

Thanks for the tips. I ordered the shorting plugs, and they should arrive later this week.

I do get radio when there is nothing connected to the inputs. I played around with putting a ferrite bead (from an old USB plug) by the phono input, but it made no difference.

When I am using the other pots, you can only hear the radio, when your ear is very close to the speaker, but it is pretty annoying nonetheless....

Thanks,

Marty
martyw OP
68 posts
 
Hi all,

So the shorting caps didn't address the RFI, even when in the phono stage. Would the next step be swapping out the moving coil stage and putting back in the other piece (I am not sure what its is called -- I think internal jumper? If so, who can do that?

Thanks -- Marty
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almarg
9,670 posts
 
Hi Marty,

Are they truly shorting plugs, which look like an rca plug and connect the center pin to the outer ground sleeve? Or are they just caps, which simply cover the opening on the jack (which I would expect would not be an effective fix)?

Assuming they are shorting plugs, yes removing the moving coil stage would seem like a logical thing to try. Presumably it comprises a small removable circuit board dedicated to that function, since it is an option with that particular amplifier.

You might ask the manufacturer or dealer how to identify it when the top cover is removed, in which case you could probably remove it yourself (while taking precautions to prevent the possibility of damage being caused by static electricity -- let us know if you'd like further advice in that regard).

Good luck!
-- Al
martyw OP
68 posts
 
Another thought, while I had the shorting plugs in -- I have nothing connected to the "outer ground sleeve" Is that the little metal piece on the back bottom of the amp that says ground?

Thanks -- Marty
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almarg
9,670 posts
 
No, by "outer ground sleeve" I simply meant the cylindrical outer part of the rca phono jacks themselves, which the shorting plugs would connect to the center pins of the jacks.

-- Al
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