I am new here but have been hearing the same cable discussion for 40yrs. Plus I am professionally trained in critical listening, I was also teaching a class when I retired. Short and to my point, just because you can’t hear it does not mean it is not happening. The placebo effect is a 2 way street! I have been arguing with EE’s all day and don’t feel like it in my off time so I will read everyone’s OPIONONS and maybe learn something. BTW Just because you modeled it does not mean it will work in the real world
That is true. For that reason, we try to triangulate the truth. We measure and look at system architecture. And we take into account years of psychoacoustics research. All of this currently points to statements regarding fidelity changes to not be correct.
Sure, if you hear noises coming from your PCs as some internal DACs and even external ones do, there is indeed a problem. But then again, we can easily measure that effect.
By the way, I don't believe placebo is the main problem. Many people who don't believe in something hear improvements they did not expect.
The issue is a much less known but even more insidious which is the elasticity of our hearing. When we are bombarded with music signals the brain chooses what it stores and remembers longer term. In other words, it is a highly lossy process. You then get a new cable and when you insert that into the system, you pay real, intense attention to what is being heard. That immediately causes you to hear detail, "air," subtle things that you were not hearing with your standard cable. None of that is related to the cable change. It has to do with changing your state of mind.
This is why when we perform the test blind and we don't even tell you if a change has or has not occurred, these differences disappear. During the blind test you will indeed hear differences but then the same difference is heard with both samples, causing essentially random outcome.
This is easy to prove. Play any piece of music on your system for a few seconds. Stop, and play it again and this time pay real attention to what is being played. I guarantee you that you will higher fidelity now! Do this over and over again and in every cycle fidelity will change! Sometimes you hear more detail, sometimes you don't even though you are playing the same track over and over again with no hardware change!
Clearly placebo is not in place in the above scenario as even knowledge of the outcome being false, causes you to still go there!
This is why the starting point here needs to be objective measurements and understanding of the system which are far more reliable than the AB test.