Interconnect Directionality

How would you like them to communicate with Houston? Sign language? 👌

So ... a theory was posited (well stated as fact), that the signal being AC (changing polarity) mattered not w.r.t. cable being not directional, and that cables were directional because energy only flowed in one direction, towards the load.  Claims were made w.r.t. current in speaker wires, and in AC wires that the current moving away from the load had no audible effect, and hence could be ignored and because of this, interconnects were directional. I expect most on this forum would not be in a position to agree with this or refute it. 

The first statement about energy transfer direction is correct, as the energy flows towards the load along the Poynting vector. The Pointing vector defined the flow of energy in an electrical circuit. The second statement is not correct. It sounds right based on the first statement but it is not.

The Poynting vector is the spacially integrated cross-product of the E (electric) and B (magnetic) fields, over the WHOLE circuit, and that everywhere current is flowing (in a wire), there are E and B fields, meaning that EVERYWHERE current flows impacts the Poynting vector. If you didn’t have current flowing both towards the speakers AND away from the speakers, you wouldn’t have E and B fields and you wouldn’t have a Poynting vector and you wouldn’t have energy transfer from the source to the load. The current traveling to the speakers and away from the speakers are equally important in defining the Poynting vector.

At a macro level, the Poynting vector is the same for both polarities of the AC signal, as the E-field is structurally the same, but as opposed to that justifying interconnects are "directional", the opposite are true outside of transmission line effects.

geoffkait17,732 posts10-13-2019 7:51amibmjunkman

You can ignore the current traveling in the direction away from the speakers, I.e., toward the wall, since that direction of current flow is not (rpt not) audible. The only direction that’s audible for any wire is the one toward the speakers. It is the speakers that ultimately produce the sound you hear. So, it’s the “quality” of the current traveling toward the speakers that is the issue. That’s why fuses sound better in one direction, worse in the other direction in AC circuits and DC circuits. As Old Blue Eyes sez, that’s life.

geoffkait17,732 posts10-19-2019 4:18pm

>>>>While that’s true, and for virtually all cables and power cords - the current alternates. 🔛 But you can ignore 😳 the current when it’s traveling in the direction toward the wall outlet. 🔜  The only direction we care about is the one that drives the speakers. That’s the direction that is audible.