I have yet to walk away from a discussion, heated or otherwise, even slightly scratched. When it comes to subjective evaluation, the tests and the documented results, I have done my homework. When separated from their pre-conceived ideas, even the very best of those (usually self proclaimed) 'Golden Ears' will fall flat on their faces. IOW, hide the stuff they are listening to behind acoustically transparent curtains. Make sure that the volume levels are set very precisely to identical levels, and I will wager whatever one likes proving that a $200 power amp can't be told apart from a $5000.00 amplifier. (Assuming that both are decent quality products of similar power) More to the point, those Golden Ears will NOT be able to tell the difference between speaker wires or green markers on the edge of CD's, or even the difference between CD players. There are (were) differences between electro-mechanical transducers. Phono pick-ups, microphones, and loudspeakers. But those, also, will astound the golden ears when they are deprived of the visual contact of their mega-buck babies when a pair of $500, well designed, speakers shit all over them.
My mentor, Dr. Floyd E. Toole shed a lot of light on the validity of blind tests. (Fortunately, that also included a blind test of a variety of scotch whiskies... again, when you don't know what you're tasting, suddenly you forget all the reasons why you're supposed to like that expensive single malt.)
I can't think of an industry so rife with snake-oil salesmen as the audio business.
r