It's actually pretty simple, Abe. It improves the sound. That is the goal, better sound, right? Don't knock it if you ain't tried it. Maybe the view of a fairly non-technical type might help. That being me, of course.
Let's just stick with physical differences and basic electrical theory for the moment. I only got as far as the second year of high school electonics, so this will be pretty basic. The cords that came with every component in my system were the standard grade 14 AWG issue. Cheap connectors, low grade wire, PVC insulation (my guess), etc. Take one apart sometime and look at the construction. It's amazing these things don't cause fires more often! The wall wiring is 12 gauge Romex and the wall sockets were el cheapo grade Levitons with push connections for the Romex; nice for a builder in a hurry, but not the most solid of electrical connections. Based on the amount of paint, dirt and dust on them, these sockets date back to when this place was constructed.
There's lots of potential problems with the stuff above, the biggest being the power cords are incapable of handling all the juice the Romex can carry to a power hungry amp. All those loose connections are bad, too. We were taught in basic electronics that efficiently moving power from one place to another required clean, solid connections and a conductor capable of carry a sufficient current to meet the load. Hopefully this is all still reasonable stuff.
After some basic system upgrading the power cables are now significantly larger and capable of carrying more of a load than the Romex. They're no longer a smaller gauge bottleneck like the original cords. They also have high grade connectors on each end which equates to a better connection to the wall socket and the equipment. The sockets are hospital grade (orange and ugly) so they hang onto a plug like nothing else. They're almost a necessity with the heavier cords if a good connection is desired. Oh, don't forget they're cleaner, too. ;-) So, now there are overall better connections at the equipment, socket and inside the wall and sufficient current carrying capacity for what the house wiring can deliver. Nothing to hold the equipment back from a power perspective, right?
Any improvements from any of this? Yes. The better (heavier) cords on the amp and pre- made very noticeable differences, especially on the amp. My guess is the 14 AWG was a bottleneck between the amp/pre- and the Romex, especially on demanding musical passages where the current draw can be very extreme. There was also a difference on the power line conditioner where the pre- and several other pieces are plugged in. Got to feed the PLC to feed the pre-,...even if it's doing nothing more than playing high priced power strip. The differences on the rest of the gear was noticeable, but mostly minor. Blacker background, more musical, the usual 'phile claims. Again, my guess is that at very least the better connections decreased things like micro-arcing, a source of noise, and resistance that limits power carrying ability. Simply going for good electrical connections and power carrying capability is still acceptable, right? To go a bit further, is it reasonable to think that using better materials or different grounding schemes can bring their own improvements? We won't get into some of the real esoteric claims as that really isn't necessary. Hopefully you're still with me and none of this reeks of voodoo.
Let's say each of the upgraded items added an average of only a 2% improvement each which is actually pretty conservative, especially considering what it did with the amp. Yes, trying to quantify these to a number is a reach. Just hang in there for now. In my system, given an average of just a 2% improvement per item equates to a 14% increase in performance for a 5% cash outlay. Not a bad investment if it's the cash that's the concern. If the average were only 1% it'd still be a good bang for the buck.
But it isn't about money with me, at least within certain boundaries. It's the music, the sound and what it does for the soul. Some things are hard to put a price on, but when a passage of music relaxes me, raises goose bumps on my arms or brings a tear to my eye it was worth every penny and all the time spent getting it just right. Making sure that what sits between the gear and the Romex was adequate did make a difference. Not all of them were big, but they add up when considered as a piece of the whole. If I owned the place there'd be dedicated circuits with better wire, grounding, fuses, etc. But I rent, so do what I can without breaking the lease. Hope, too, that this was helpful in some way.
PS - Most of my cables aren't colorful. They're mostly all black. Wish the speakers cables were...instead of purple!
