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And with that, I'm out of my depth. But thank you.
It sounds like we are dealing with relatively minor influences here though (tenths of a db). Do you think this would be audible? Also, can you address the last part of my post, if you know - regarding similarly constructed IC's with only changes to the conductor metal?
Don't forget, while .1 dB by itself is not distinguishable, one must consider an interchannel difference, not an absolute one. What we are trying to discern is image placement relative to other images. Most researchers confuse the two. I've not stated that .1dB is the effect level, just that I would recommend the measurement tools be capable of that level of accuracy and precision in addition to the 5 uSec entity (which I would recommend 100 nSec precision). I am not interested in equipment which has a resolution equal to the measured entity, but rather, at least an order of magnitude better if possible.
Ah, the last part..sorry.
The metals used can alter the permeability, resistivity, and geometry. If a magnetic wire is used, the internal inductance becomes much higher which affects the cable's characteristic impedance. This alters the breakpoint frequency where current will share 50/50 with the line cord neutral/ground, as well as with the other IC. Granted, it's only 15 nH per foot, but a high capacitance cable will be affected more.
The resistivity of the shield determines the amount of current which will flow in the ground loop, and will again affect the 50/50 breakpoint frequency.
The geometry of the shield determines the inductance of a coax...a spiral shield of course, higher L and higher R.
Honestly, I wouldn't worry about a choice of silver over copper, it's trivial.
Worry about the equipment...that is where the real problem arises. Unbalanced input/output audio equipment does not meet EMC design at all..and balanced is a tad better, but not much.
A well designed system will be invariant to the choice of IC's and PC's. Any alteration whatsoever in a system as a result of wire changes indicates that the equipment has problems.
Personally, I use the IC's and PC's that come free with the equipment. If I find any issues with my wire selection, I generally fix the equipment or re-layout the wires.
ps..added a jpeg showing the calculation of the ground path reactance for a simple one IC system. The electrical diag shows the basic elements the return current has to choose from to get back to the source.
Cheers, jn