Originally Posted by IPodPJ
Ok. I will.
Actually, I think thats what the foil might be doing. Just like the magnets on the cable are supposed to create a field that accelerates the electron flow, I believe the following could be happening:
1) By wrapping the foil from magnet to magnet, it is widening the field somehow and accelerating the electron flow even further.
More likely:
2) By wrapping the foil from magnet to magnet, the stray EMI all around the cables are gathering in a field around the cable, accelerating the electron flow via magnetic induction. (There was a recent article in Popular Science about Wireless electricity using magnetic induction at a given frequency.) If this is the case, depending on the levels of EMI floating around you might experience variable results during your listening session.
The workaround for future generations of cable:
If in fact #2 of the above is what's happening, it would make sense why a certain cable company has power supplies attached to their cables. This would provide the benefit of the foil without the EMI uncertainty factor.
Try Google Faraday Cage, and EMI ferrite. Aluminum foil are non-magnetic. So what you have constructed is a Faraday cage. However for a Farady cage to operate properly, the shield needed to be grounded.
The magnet used on the cable is to reduce emission. It is also used in some power supply cable to reduce emission from the switching power supply. These are part of the FCC requirement.
One of the great test for RFI/EMI is to use your cell phone. Just call someone and the put your phone along the cable, connectors and equipment. The interference will sound like a noise, not reduced high or low. It is very distinctive. If you don't hear anything different, then you don't have any problem.
You can do the same test with cheap powered PC speaker. You can definitely hear a noise coming through.