The place I see ferrites most often is video cables for PC monitors. In my previous response I should have made clearer that I was speaking in theoetical terms that a ferrite
could be used to certain cercumstances to reduse noise over a cable, not as an endorsment that you should. And I do have to admit that I do not use them anywhere in my system.
It is always a very delicate balance trying to filter out noise without over filtering and pulling out transient information that is part of the signal. Pete is the man when it comes to power cords so when he says ixnay on the ferrites that carries a lot of weight in my book. But if you are really curious just google ferrit beads and you will find doozens of places on the net that well sell them to you for a couple of bucks a piece. They easily snap on and off so you can see for yourself. just make sure you get one big enough to fit around the cable you want to experiment with.
Ferrites are generally a no-no with audio, but if there is one thing I have learned in this hobby it is to never say never. And if you can pick up the parts without forking over a fist full of dollars sometime it is fun to experiment, even if ther is a 99% chance that it won't work.
(Kind of like why we play golf. The one percent of the time we make a really nice shot makes us forget about the 99% of the shots that we screw up.
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