I don't want to beat a dead horse but I'm bugged.

@clearthink

Let me restate. You can compare the frequency response of headphones to speakers. You can also jump off a tall building. Doing the latter without a parachute and the former without applying appropriate corrections are both bad ideas. Are you advocating bad ideas?

I really got into headphones when travelling extensively pre-Covid.

The graph above, the Harmon Preference curve, is based on in-ear frequency response of over-ear and in-ear head phones. If your headphones match this response tested with a dummy head, then they will approximately match the response of a good flat on axis speaker in a room.

Perhaps you should not make insults like this,

I suggest you familiarize yourself with these common practices so as to avoid your misinformation.

when it implies you are providing accurate information, when what you were doing is misleading due to inaccurate or insufficient information.

It’s curves like this (there are several variants) that headphone designs nowadays target. Maybe we should do something similar for Amps plus speakers.

To the original posts author, I think we do that already. It is called flat though it may relate back to the Harmon in room preference curve. That would be worth checking out again.

I'm the opposite.  My system sounds really good to me, the best sound I've acheived to date, so I'm scared to run REW and find out I'm wrong.  I'm also scared to upgrade anything and screw it up.

And so, I'm told to rely on measurements, both my SET amps total failures based on high even order distortion. And then we have my SMSL amp I use for burn in purposes. I have no doubt the SMSL measures better than both SET amps, so is the vastly inferior sound quality of the SMSL a total figment of my imagination? Hilarious! Even more hilarious, take this couple hundred dollar amp, class D design and compare it to multi thousand dollar class D amp, both measure pretty near exact. Does measurement acolyte believe SMSL sounds as good, lets say Atmasphere class D?

I wonder if megadollar car owners spout the same stuff when a Tesla 3 (properly equipped) dusts them at the light.

I don't think an accurate amp is expensive to make.  Technology progresses. Pay more and you pay for different or more power.

If we reach a point where sound quality can be accurately predicted by measurement I’d have zero resistance or issue with it. My point is acknowledging we are not remotely close to doing that now.

@charles1dad 

I would tend to believe amplifier designers who are building the upper shelf equipment, over the general public.

Measurements tell me next to nothing in regard to how these audio components will sound,  so I must hear them. I totally understand if others judge and select differently with buying audio components.  Do what suits you the best. 

However, the upper shelf designers seem to make stuff that does not require cabels to serve as tone controls. So they seem to know how it will sound by looking at the graphs. Just because 99% cannot, does not mean that it is impossible.

I have a couple of tube amps, and tube preamps… and I know that they colour things.