Spectral preamp picking up a radio station


I have a friend with an all Spectral pre/amp system (25 years old). When I was listening to his system, I can hear quite distinctly  some radio station playing from the left speaker even though there is no radio on in the house. We were playing an album, so it can't be the DAC. This started happening within the past year or two. Could a malfunction in the preamp cause this?
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The frequency band used for AM is not that high (550Khz to 1720Khz). The Spectral preamps of that age were designed with ultra-wide bandwidth, but I assume had some form of RFI filter on them to prevent this kind of interference. It's possible that a capacitor in this circuitry has gone bad which is now allowing these signals to be picked up and modulated the output signal. 
Spectral is notorious for being "high bandwidth" which also means possibly high noise picked up.

It may also be a function of new interconnects.  Try disconnecting all of them. If that fixes it, consider shielded IC cables.
No component has been changed over the past 20 years. It was fine until 1-2 years ago.
You get a tuner for free. What's wrong with that?
The problem is it's not a tuner. A tuner let's you, uh, tune to the frequency you want. Something they used to teach everyone back in the 50's, before education got so dumbed down nobody knows anything any more but false facts and jokes. Oh well.

I am not kidding. Common grade school project was to build a crystal radio. So as a little kid we learned about radio waves being everywhere, picked up by every wire. The trick is to tune to the frequency of the radio broadcast you want to hear. So OP does not get a tuner for free. But he does have something in there that is doing the tuning for him. The solution is to find it and either make it stop or eliminate the source getting to it in the first place.  

This really is no different than what happens all the time with phono inputs. It's not uncommon to hear radio broadcasts come in frighteningly clear. This also shows how in spite of what so many guys think RFI is everywhere, all the time. Usually it is sort of like a uniform white noise that no one really notices at all until we do something to reduce it. Then it's crazy how big the improvement can be. 

Okay that should be enough to guide you to finding the problem- its just like tracking down any other source of noise.


Jeez MC, lighten up. Let me say this very clearly so that even you will understand. It Was A Joke. Pot calling the kettle black.
Regarding RFI, I've been using phono stages for 46 years and have never once heard radio interference. Guess I've been lucky in that regard.