One of the problems with these type of conversations is that it's all opinions with no data of any kind except for empirical observations, which are variable at best; and self-rationalized "facts" at the worst in support of a personal point-of-view.
As someone who has worked on a number of electronic systems and provided or worked with a variety of instrumentation systems, you find that "observer bias" is a huge problem in discovering problems, verifying operational parameters, or testing equipment.
I will give one example. I had a custom built three-channel image processor mounted in a VME chassis. I was having a number of problems with it and traced the problems to the chassis power supply, although I could not determine the cause of the problems.
I took the power supply to the electronics engineering group who tested it and verified the output voltage as correct and the current supplied as also being correct - and told me there was no problem with the power supply.
They had tested it for performance for predetermined problems - ones that they had seen as being within a "normal range of problems." That is the observer bias - not looking beyond their own built-in bias as to what they imagined would be a power supply problem.
I talked with a software engineer who also had a masters degree in electrical engineering. He said, "Let me look at it."
About an hour later he came to me and said, "I've found the problem, let me show you." He had found a 250 kHz signal modulated onto the power sine wave.
He found it because he didn't have preconceived ideas about either the potential problems or the results he wanted to find, so he looked at the power supply output with a completely different set of test equipment than the electronics engineers.
I've used that lesson for years in not approaching things with a preconceived idea of what the results should be, and also not being closed minded in setting up tests and equipment to only find or verify the results I want to find.
In these threads you find two opposing points of view, and generally, neither side has any facts based on unbiased testing - so you find people talking past each other trying to make points without listening to the other side.
Me? I have no preconceived opinion on whether audiophile products work or don't work. To that end, I have expensive cables, interconnects, etc. - and I am always hoping to hear a difference, which, I'm afraid, I never really hear.
I would love to test the audiophile products, but I don't care enough to invest in the test equipment suite required to fully find out whether these things work, don't work, and investigate them for performance characteristics beyond what's being advertised as the "expected performance improvements."
Much like the 250 kHz signal modulated onto the VME power supply output, there may be things going on beyond what a biased observer may be expecting.
