@crymeanaudioriver said
“If a power conditioner has no effect on the output, or a USB cable has no effect on the output as Amir had shown in tests, then how could the sound of the system / room possibly change?”
This statement assumes Amir is testing all possible phenomena that effect sound quality. I do not believe this. Feel free to believe he is if you want to, but don’t insist I must believe what you believe.
My belief is not anti science because science is about observation and discovery. In my opinion, your position is about stagnation and your belief you know everything there is to know.