Killingbeans
Major Contributor
I think I'll clarify my original question: are the measurements fully describing all the aspects of the physical waveform?
Even the most complex and dynamic music is nothing but a sum of sine waves. Literally nothing. You only need an oscilloscope to see everything the physical waveform has to offer. And maybe a spectrum analyser just to make the variations more visible.
I think what you are really asking is whether the measurements shows us every single difference between an input and an output.
I wouldn't worry about it. If you play a digital file through a chain of gear and capture the output with an ADC (just to ad salt to injury), chances are that when you do a null test on the two files, the difference will equate to hearing an ant fart on the opposite side of the planet.
So no, they don't tell us everything. But they tell us all we need to know, if we don't want to waste our time
The real question is at what point do these errors matter?
When they become significantly louder than the ambient noise floor. Probably a pretty rare occurrence.