I was trained and worked as a scientist for over ten years... but never stopped being one. When it came to high end audio, I learned about a few of the important technical aspects and I then quickly realized what a small part of the whole picture they painted. Thereafter I did not waste a lot time on trying to dig down deeper into layer after layer of variables. Over the ensuing forty years I have thought about this quite a lot, and of similar problems. I was also a a professional "inventor" (mechanical / electrical engineer) soon after college. I learned the same thing. Variables quickly add up to be an insurmountable obstical to using science to analyze and use as predictor. You would end up doing a PhD thesis after thesis and never get anything accomplished. There are too many variables to determine what a system will sound like or what components to put together to get the sound like. No doubt Transparent (the company that makes high end cables) has engineers using science and material experiments to create their cables and interconnects. But in the end it probably still comes down to pragmatically trying stuff at some point. It certainly does in component design.
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Consider also the music you are listening to and trying to evaluate. It is not a single tone. If you were to listen to a single tone and compare systems that would be one thing. But music is dynamic... if you listen to a recurring drum beat...it is influenced by other instruments... also your minds eye (ear) bounced around. So even one note has arrival, decay, tone. There are harmonics influencing. This is why just listening to the music for an extended time to determine how much you like a piece of equipment is usually the best way for normal humans to decide. Flitting from sound to sound only gets you a sample and just compares some gross differences... unless you are a very talented and experienced professional reviewer.
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Consider a system... multiple components, each influencing each other... and that includes cables influenced by magnetic fields induced by currents. Each component is composed of dozens of subcomponents and each brand of capacitor sounds different. The designer of one of the most expensive and prestigious high end electronic companies said, that he can make a component sound exactly like he wants... if he wants it warm... he uses these capacitors and these resistors and if he wants it this way...this brand... same capacity and resistance... different materials and construction. It is simply in the real world with this many variables it is not worth the time for people in companies and enthusiasts to spend the time and resources on developing incredibly complex models to encompass everything in assessing and predicting based on hundreds of interacting variables. I am sure as time goes on more and more understanding occurs. But for now. Everyone uses some basic variables and then rely on what they hear to develop and pragmatic working understanding of the electronics and what stuff sounds like.
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Sorry to have composed this so quickly... but it is getting late. This is a topic one could do a PhD thesis on.