master / slave digital cable for 440Pro

[JensRoland]

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It is also worth noting that the Audioquest Carbon cable supplied for the master companion link is directional, and if you use the inputs on the companion, this cable has to work in the 'wrong' direction.  Oh the utter horror!

Think of the poor electrons, struggling against the arrows...  That's bound to cause all sorts of upset timing between the two units.    

I have asked AudioQuest about the directionally of their cables in relation to Devialet master/Companion use - here the reply - best wishes Jens:

The directionality of the cable is an interesting one, when we make our copper based cables we extrude large bar stock of copper into a long small conductor. Doing this stretches out the grains that from the copper, changing its internal structure (that sounds like snake oil, but google it, its quite interesting). This has 2 impacts on the cable. First, with a smaller number of longer grains there are fewer barriers to the signal as it passes along the cable. Second, it affects the resistance the cable gives to external RF interference in one direction, versus the other. Thus the directionality is less about the signal itself, and more about how interference can be most efficiently dropped out of the cable, and the resulting impact that has on sound.
 
In a perfect world, such a cable would only receive a signal in one direction. However, modern electronics are a lot smarter than they used to be, and Devialet is a good example of this. 
 
The Carbon cable is a copper cable, with 5% of its diameter being silver (the silver is on the surface of the cable, where there is 100% current density at all frequencies). In this case, reversing the direction would sound slightly different. However the Wild cable is pure silver, which has less of an issue with Grain structure, and is also extremely well shielded against external interference (the Carbon has 5 layers of foil and carbon shielding, whereas the Wild has 7 layers and improved EMI absorption).
 
Therefore directionality of a Wild cable would be less of an issue in such a setup than directionality of a Carbon cable. However, as is always the case, trust your ears and experiment!