That is a interesting analogy and I respect your opinion. I fail to see the correlation between a person who attends a opera and sings part of the opera to his wife and of a recording of a headphone for playback. I do see where you are going with your statement. I can say this I have watched numerous videos of reviews for noise canceling headphones online. I then purchased several types (see attached picture) over the past two weeks, I already owned the Bose Quiet Comfort 35's since 2016. The remaining 3 have recently been purchased. The microphone used to record the sound and the playback speakers come into play. The reviews for the Apple Airpods Max and Bose 700 headphones I watched online, I experienced the same listening tonal qualities in person that I watched online. Another example when I was looking to upgrade the exhaust on my 2018 BMW M5 (F90), I listened to numerous reviews and one could tell when a low quality microphone was used. There was one review that was professionally done for the Remus cat back exhaust that was spot on sound wise. I now have the Remus on my vehicle and it sounds just like it does on line.
Car exhaust is a bit different beast, but lets go back to headphones and speakers:
Lets say YOUR speakers are tent be overly bassy and have poor soundstage, listening to other speakers playing THROUGH your OWN speakers - they will all sound the same. I hope that this logic isn't lost on you.
Yes, Z posts tons of SUBJECTIVE reviews for headphones and he may be not entirely wrong, but everyone has a slightly different head size and shape, ears, expectation of comfort, etc... The best way is finding RIGHT headphones is to understand some basic design differences and then try a few out.
One thing I will say is this: I own way too many headphones and one brand which yet to disappoint even once is Sennheiser. They are always delivering sound quality at or above their price points. In fact, my best phones are HD600. I also own Austria-Made AKG-712Pro which used to sell for $500 and HD600 sounds better to me. (AKG is a bit more comfortable thought)
One of the hugely popular headphones ATH-M40x is one I absolutely hated the bloated and overly bassy sound, but maybe someone who likes modern rap/hip hop may just like these.
