Best interconnects & speaker cable? I don't get it


I don't know if there is a question here but I'm posting this to see if there is something I'm missing or overlooking in this observation. To the point, I've read many posts arguing the benefits of one or more conductors over others and I almost understand some discussions regarding, at least, comparisons of wire gauge for speakers. Maybe it relates to my less than well developed ability to discern subtlities in sound quality but I really can't hear much, if any, difference between interconnects or speaker cables.

As an example, I was recently experimenting with an amplifier selector (Niles DPS-1) which can accommodate a max of 14AWG speaker wire. In doing so I had to disconnect my existing cables which are "high end" 12 gauge per leg bi-wires. In making this comment I realize that just because my old wires are big and expensive does not necessarily mean they are the best match for my system or even any good. But...even though I think I am able to hear some small difference between them, to say that I think one is better than the other would be a stretch.

It seems to me that there are factors that would logically lend to the issue of quality, the primary of which would be conductor resistance and/or impedance. However, for transmission of line level signals, I can't see impedance as a significant factor.

All that being said, I believe that some listeners with acutely honed abilities can actually hear these differences and, in a way, I am somewhat glad that I don't; It makes wire choices much easier and way less expensive.

My current system consists of Shanling S-100 CD player, CALSigma 2 DAC, Rogue Audio Sphinx and Martin Logan Odyssey speakers with various interconnect and speaker wires.
128x128broadstone
My personal experience is that A/B tests often show little difference, but differences do become apparent with extended listening.
Schubert (are you Death or are you The Maiden?) if your stereo 'seems' louder when it is dark in the room, surely you can see that as evidence that non-acoustic factors can seriously affect our auditory perceptions. That alone should make you at least wonder how 'real' any of the subtle differences you, and others, hear are. As long as you know what's playing, self-deceptive desires and prejudices can easily enter the equation. Blind testing is the only known method for removing listener prejudgments.
I suggest, especially if the amounts of money involved are substantial, that you actually grab a friend and have him or her switch components as I have outlined in my first post above. If you pass the test, if you find you can, without knowing what you are listening to, reliably tell the difference, then you will have reason to feel confident you are not just 'believing what you think' against the evidence.
But if you fail, as has virtually everyone who has ever tried this experiment, you will have gained important insight into not just audiomania but also into the workings of the human mind.
Adding to my last post, I too hear and have always heard phenomena such as Schubert describes. Once I noticed that the system sounded 'better' when I switched around some particular cables . Then I noticed it sounded better again when I returned the cables to their original positions. Huh? This is known as psycho-acoustics, a well known phenomenon in which auditory perceptions are influenced by non-acoustic factors. I learned over the 55 years since I assembled my first system that any number of things, known and apparently unknown, can affect my sense of what I am hearing. That alone meant that I would be foolish to accept necessarily as true whatever I hear. If my system sounds better or has 'more detail' or a 'deeper soundstage' with my eyes closed ( so I KNOW that nothing has physically changed but the orientation of my eyelids) why should I believe that I am hearing real difference without the kind of objective verification available (admittedly only approximately) through blind testing.
This pursuit of sound is an expensive habit, potentially causing some people serious financial difficulties. Obsessing over a set of wires you can't afford to the point of blowing the kids' lunch money on it since you think they 'improve' your sound is a sure sign of addiction and that alone can seriously color your perceptions.
If you want to have at least a little basis for trusting (or not) what you hear the simple single-blind test I have described is not only fun but it might seriously symplify your life.
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Rpfef, I'm death.
You are dead wrong. What it proves is in a human brain sight and sound are interrelated , in a way/ways we have no knowledge of.
"Evidence" is for trials, human heart and soul are for music.
There are more things in heaven and on earth than we can dream of, to paraphrase an English gent.
And there are things worse than second-guessing yourself,
but not many.

No need to warn any of us about our spending habits, any "phile knows in his heart of hearts we all have more than a touch of OCD.
I took up audio to kick heroin myself .