Yes I have posted on this before, and no my views have not changed. The power cord is part of the connection between boxes, a conduit for picking up external noise, radiating noise and part of the electrical resonances formed with the components and wiring in the walls etc.
All of these aspects can be modified by the materials and construction of the power cord. In any situation there are multiple ways in which a power cord is interacting with the system (see above list), these interactions are going to be different in every system. Well I suppose if you had a system that was in an environment that had NO RF fields at all in the area, and EVERY component plugged into the house injected NO noise into the system and EVERY component plugged in had NO resonances in it's power circuit from DC to hundreds of MHz, then maybe you could say that a power cord had no theoretical way of affecting a system. The probability of that happening is EXTREMELY low. So I'm going to say that in any real world situation the differeing electrical properties of different power cords will have some affect on the system. This affect is going to be different for every system so its almost impossible to predict what particular type of cord is going to be best with any particular component and system. In addition you frequently wind up with a situation where something that cuts down on lower frequency interactions between components (say 100KHZ) may increase the resonances at higher frequencies (say 10MHz). As to the response about the wiring in the wall, power cords can be very important with that. The wiring in the wall is an unterminated transmission line at RF frequencies, the power cord plugged into a componant can play a MAJOR role in how that RF gets coupled into a component. This one is actually quite easy to see. Put a spectrum analyser (with appropriate high pass filter so the 60HZ doesn't go directly into the input) across the primary terminls of the power transformer. You will see LOTS of stuff there. Try different power cords, those patterns will change significantly. OK, so what about using a power filter? You still will have a fair amount of stuff. It WILL be less in some areas, but no design is completely effective and for many of them it actually gets worse in some areas. The power cord will STILL make a difference. Certainly not the SAME difference. This is just one aspect of how power cords intereact with a system, there are many more. And of course every system is going to be affected by these changes in deifferent ways. In one system these RF differences may make a significant difference in sound and in others it may not. Same with other interactions a power cord can have. Please note: I am NOT advocating $1000 power cords! I AM saying that power cords CAN make a difference, and these differences can be heard with inexpensive cords, it does NOT take super expensive ones to make a difference. So if you are into trying to get the best sound possible out of your system its probably worthwhile to try some different cords in different locations in your system and see if it makes any difference, it might make no difference, or you might be pleasantly surprised by the improvement. Because of the complex intereactions there is no way to tell without actually doing it. I think the best way to do this is NOT to buy "audiophile" cables, but go to a computer store, a hardware store, a department store etc and buy 5 inexpensive power cords from different manufacturers, the probability of them all being exactly the same is low. If you do this you won't run into the "the expensive cord has to sound better" phenomanum because they are all cheap! Try them in different configurations and see if you notice any difference. In my system I CAN hear differences in power cords, even with the transformers damped. Its not huge, no night and day difference, but its there and has been worth while, the system sounds a little bit better and it cost about $100 to do the testing. For me it was worth it. John S. -- JohnSwenson ------------------------------------------------------------------------ JohnSwenson's Profile: http://forums.slimdevices.com/member.php?userid=5974 View this thread: http://forums.slimdevices.com/showthread.php?t=88364 _______________________________________________ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/mailman/listinfo/audiophiles
