I have heard that it is most important to match speaker cables with the Amplifier being used; more so than the speaker.
That’s a new one to me. The whole idea of matching with cables is based on a false premise. The idea is that nothing is perfect. (True.) So what you are supposed to do is match up components with flaws that compliment each other. A speaker that is bright or forward is matched with a cable that is more mellow or laid back. That kind of thing.
This is where cables get the bad reputation of being tone controls. There are lots of crappy cables and they can indeed be used that way. Actually most of them are bad enough they pretty much have to be used that way.
This whole concept of matching this way is what I call the band-aid approach: the problem is still there, you just covered it up. What makes it hard to learn is you really can build a pretty nice system this way. Only problem, when you want to upgrade something, every really good component you try is only going to reveal all the flaws you have built into your system. Its a recipe for constantly upgrading.
Please notice how many audiophiles are constantly upgrading. There’s a reason, and now you know what it is.
A better way to go about it goes like this. Your Krell and your Harbeth, they each have their own individual set of strengths and weaknesses. Your job is to find the cable that best illuminates all their strengths AND weaknesses. The cable that best reveals everything they are doing. As well as everything else in the signal coming down the line from your source.
Once you rip the band-aid off and shift to this perspective then its real easy to realize the best cable is the best cable, period. Does not matter what amp. Does not matter what speakers. When you upgrade, no matter to what, you will be happy because the same wonderful properties in the cable that shined a light on your Krell and Harbeth will now shine a light on the new gear. You will be off the audiophile treadmill. Hardly ever will you be disappointed with a purchase. You will be happier and more pleased with your system as the years go by.
Or you can listen to the system matchers. The choice is yours.