The inherent flaw of any sort of blindfolded A/B testing is when there's unfamiliarity of the test subjects with the items being tested. For example - a blind taste test of Coke vs Pepsi is adversely affected if the test takers aren't cola drinkers. Without a recognizable frame of reference, "best" or "better" is merely a guessing game.
So, playing a piece of music the subjects don't know on a system that is not like their own and asking them to compare that sample to a slightly changed subsequent sample is a waste of time, not a universal truth. Most of us have several pieces of music/performances/albums that we know intimately. If the benchmark used is one of those on our systems (or an equivalent one), then comparative testing has validity, but only then.
Amir and Blind Testing
Let me start by saying I like watching Amir from ASR, so please let’s not get harsh or the thread will be deleted. Many times, Amir has noted that when we’re inserting a new component in our system, our brains go into (to paraphrase) “analytical mode” and we start hearing imaginary improvements. He has reiterated this many times, saying that when he switched to an expensive cable he heard improvements, but when he switched back to the cheap one, he also heard improvements because the brain switches from “music enjoyment mode” to “analytical mode.” Following this logic, which I agree with, wouldn’t blind testing, or any A/B testing be compromised because our brains are always in analytical mode and therefore feeding us inaccurate data? Seems to me you need to relax for a few hours at least and listen to a variety of music before your brain can accurately assess whether something is an actual improvement. Perhaps A/B testing is a strawman argument, because the human brain is not a spectrum analyzer. We are too affected by our biases to come up with any valid data. Maybe.