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
Hi Al,

You are probably right but if Marty has some ferrite beads it won't cost him anything to try them on the speaker cables and or the power cord. Maybe the radio tower transmitting antenna is close to where Marty lives..... Or maybe it is a hi-power radio station.

The amp received a good review from Stereophile and I can't imagine the proper shielding was not incorporated into the design and build of the unit.

Is it possible the amp could sound good and still have a cold solder joint somewhere along a signal ground path?
Jim
Is it possible the amp could sound good and still have a cold solder joint somewhere along a signal ground path?
Yes, that certainly is conceivable, Jim, although of course it would be very difficult to troubleshoot.

Marty, I realize that this is all probably moot, because you are proceeding to look for a replacement amplifier, but I see in the thread that you started today that you actually did mention nearby radio transmitters. It would be interesting to know how far away they are, whether they are am or fm, how many watts they are (perhaps that is indicated on their website), and if when you hear them through your system you hear actual music and/or voices, or just static-like interference.

Regards,
-- Al
Hi Al and Jim,

Not sure how far away they are, maybe 1 mile? The signal is FM. Besides the amp, the only thing that changed is the speaker cable (from wireworld biwire to DMN single run). Interconnects and speaker cables are the same.

Figured the easiest thing at this point is to quit while I am ahead, sell it, and find an amp I can demo at home first.

Thanks,
Marty
Hmm ... It's hard to envision how an FM signal could be detected/decoded by your integrated amplifier into something resembling intelligible voice or music, assuming that is indeed happening. AM would be a different story, and more easily explainable.

A home demo of the next amp certainly seems like a good way to proceed. Good luck!

-- Al
HI Al,

Couldn't the rca inputs act as an antenna? Or could it be the speaker wire?