Not saying that everything and anything is placebo, but in the cases where the only argument people have for an effect being real is "science doesn't know everything yet!", it very likely is just that... placebo.
well, if you can "imagine" how a speaker !exactly! sounds just based on graphs we can talk again, and it certainly is not just frequency response in db
while looking at the tedious research people have made into the actual limitations of human hearing
you really think this is a closed book? (i mean the perception of the auditory (ear/brain) system as a whole, not just "limitations")
because if i listen to an unoptimized system i get rather quick a headache (specially at higher volumes).... and dont say placebo now.... specially audio source/usb connection/opamps/mainsfilter has an effect on this but not only, basicly as the audio gets "clearer" it will produce less ear/brain fatique, for me this is a clear evidence, tho you dont have to believe me
also treble has an big effect on this BUT as the setup gets "cleaner" you can turn the treble up again without negative effect
tho i would also like to know why this isnt exactly measureable in any kind of form (at this point)
I've been there. I've spent decades obsessing over the "sound" of op-amps, capacitors and all other kinds of components. I based my ideas on countless campfire stories woven from subjective impressions. I didn't stop to consider whether any of it had been verified in a reliable manner.
so, once you heared a meaningful change in those things and at some point not anymore?