Interconnects, some have directional indicators, why?


I'm curious as to why some interconnects are directional? Is there a physical internal difference and do they generally sound better and cost more than non-directional cables? Thanks for your interest.
phd
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Well, thank you Ron, I will look into that right now, it should make for an interested read.

mihorn,

My post was in response to this part of your post;

That includes fuses in > 30~40 years old vintage gears. Switching the direction of the fuse, the electrical current takes longer time (and subtle) to hear the effect because many active parts have to react to the change of new current (unlike audio signal). In my experience, it usually took 1~10 minutes to hear.

AC current is not flowing through the fuse. Energy is, in the form of an electromagnetic wave.

I think if you guys that have experimented with fuse direction, and can hear a difference, it is hard to justify if one believes AC current flows back and forth though the fuse. If that was the case then the fuse would have to act as a diode in one direction to hear a difference. What other reasoning can you use?

If you use the theory, energy travels through the fuse in the form of an electromagnetic wave from the source to the load, then the next question is how could reversing the fuse make a difference?


Here is what herman posted again:

If you say the AC fuse blew because there was too much current flowing

through it everybody nods in agreement even though that isn’t true. If you

say the wire in the fuse melted because it got too hot after absorbing

energy from the electromagnetic wave people look at you like you are

insane and want to argue that vibrating electrons constitute current flow.

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The issues of fuse directionality and cable directionality involve numerous factors that are different, and discussions of the two issues should not be commingled IMO. Some of those differences are:

1)A fuse has just one conductor, while an audio cable has two or more.

2)The lengths that are involved are vastly different. Most cable parameters, and arguably most cable effects, are proportional to length.

3)An audio cable conducts an audio signal. In the majority of applications a fuse does not.

4)The nature of the contact surfaces that are involved in the two cases is very different.

5)If all wires are directional to a degree that is potentially audible it would seem expectable that the directional effects of a fuse wire would be swamped by the directional effects of the vastly longer associated wiring. In the case of a mains fuse that would include the wiring in the power transformer, the AC wiring within the component, the power cord, and arguably even the AC wiring inside and outside of the house.

6)Regarding empirical evidence that has been asked for in some of the posts above, in recent fuse-related threads Ralph (Atmasphere) has cited experiments he has performed which have determined that the same effects resulting from changing the direction of a fuse can be accomplished by rotating the fuse in its holder. And probably even more effectively. In both cases dimensional imperfections in the fuse and its holder result in differences in contact resistance, and consequently voltage drop is measurably and audibly affected.

FWIW my comments on fuse directionality have been provided in various recent fuse-related threads. See for example the first of my posts dated 10-28-2016 near the middle of this page.

Regards,
-- Al