Cable directionality


I'm sure this has been discussed before but I missed it, so what is all this stuff with the direction of voltage flow with cables? Every cable you see any more has a little arrow on it. Since the signal is AC and travels one direction as much as it travels the other, what difference could this possibly make. I have talked to numerous co-workers (all electrical engineers) and they ALL say this is the biggest bunch of bunk they have ever seen. Since I am the only "Audiophile", I try to keep an open mind(I'm also the odd man out being mechanical.) Skin effect, resistance, capacitance, etc. are true issues. You pass power through a wire and it creates a magnetic field. You do deal with impedence and synergy with the driving source. How about a few technical answers from the audiophile community.
bigtee
BigTee, you are confusing a "shield" with a "ground". They can be two different things. In some cables a "shield" is connected only at one end. There are still two other conductors to carry the signal. There is no mystery here to anyone who has ever worked in a calibration lab!
Sorry, but I can't help but be somewhat amused by this thread (and ones like it). I know next to nothing about electricity and circuits, so all I can do is humbly take note of the fact that no one yet in this discussion has claimed to have either heard the supposed difference flipping their cables around, or to have tried it and failed to hear a difference. Well, neither can I - I guess I just don't care enough to have bothered (and I'm quite willing to entertain notions of marketing-driven audiophilic excess here). But what I can say with certainty is that I haven't been able to learn anything for sure from all the confusion and contradiction above. Can it be that the engineering side of this hobby contains even less clarity and consensus than the listening side?
Zaikesman ... I'm an electronics engineer. We engineers are always being bashed on this board for being closed minded to what audiophiles have "heard with their own ears".
For once I am inviting explanation for something I am extremely skeptical of (directional AC carrying cables) and now you accuse us of lacking clarity.

It would have been much easier to state that cable directionality is utter bullshit for an AC signal. For a pure cable I think this is certainly the case. However in the case of interconnects I had previously overlooked the grounding issue. I'm wondering if I have similarly overlooked something in speaker cable design.

What do you audiophiles want from us engineers ? Clarity, or open-mindedness ? Please make up your minds because it's getting awfully confusing.

For the record I have tried it, but failed to hear any difference.
I have direction all speaker cables, and I have tried. I didn't hear anything, but i wouldn't be surprised if on some systems, it turns the sound South.
Bigtree - Here is why your single-wire scenerio worked: The return current for the signal was running through the ground of the power cords of the two components. This is simply batteries and bilbs. The current flowing in the signal wire must return on another wire. The optimum scenerio is that the wire is identical in length and type and running alongside the signal wire. This will minimize noise in the signal. If you dont run a current-return wire, you risk inducing a lot of noise, like your radio station for instance, or 60 Hz hum. As for shields that are unconnected, this is only possible in cases where there is already a signal and return wire present. There is no current running in the shield because it is only connected at one end and this provides a partial "faraday cage" that will prevent EMI from being picked-up by the internal two conductors.