thyname
Because everyone measures stuff at the analog output of stuff. It’s like measuring the sperm count trying to diagnose ALL diseases
You are mistaken. We do not have to diagnose all possible diseases of an audio system. On the contrary, to avoid significant complication of the matter we should regard an amp and all its wiring as a black box with just input and output.
The measurement devices allow us to analyze the difference between electric signals of the input and the output with precision that exceed our hearing possibilities quite a lot.
With proper measurement we can be sure that on the output (on the speaker terminals) there are no RF signals or audible signal distortion and all the more that nothing is changed when we reverse a single wire (see article by Douglas Self). After that, we can say with confidence that the acoustic signal will also not have any interference associated with wires and cables coloration and directivity.
As a result we face the paradoxical situation when we hear what is not presented in the signal. IMO there are two possible ways of thinking about it:
1 - Psychoacoustics and medics are wrong about hearing sensibility. But here we contradict thoroughly checked scientific data derived from the best organised subjective tests ever. And we contradict logic, because wires/cables audibility is perseived against the background of relatively loud noises. Why white noise at -50db level does not mask the microsounds that presumably occur at -100db level? There is no logical answer to this.
2 - Simultaneously with an acoustic signal we perceive some still unknown type of information using sixth sense. No matter how crazy it sounds, this is the only logical explanation for the phenomenon so far. And by the way, the many references about inconsistencies in scientific theories of hearing that Mahgister provided us make this assumption not as crazy as it seems at first.
It would be nice if you suggest another logical explanation of the matter for a change.