1dB is enough for me. But "flat" is a joke, because the step is audible as an impulse anyway; signal theory. And the feedback after each trial doesn't make much sense either.
Otherwsise, are you satisfied with the discussion of the original topic, is it a fun question as somebody pointed out?
Waht are you aiming for, you're on a shopping tour?
I apologize for the long winded reply
In a very ignorant state I started a week ago with the assumption that what
@traind hoped was not true actually was true - speaker manufacturers are selling snake oil. Further I believed then and still believe now that there are speakers out there for about $1k that are so good that in a blind test audiophiles would pick them over much more expensive speakers. For discussions sake I'll call that the Point of Diminishing Return at which one thinks spending more won't achieve audible difference. Now that idea can be refined in a multitude of ways, but that was my general idea, and I started a poll to see what folks here thought. Along the way I've come to see 2 things. First the vast majority of audiophiles put the number much higher than I did, and so I'm more than willing to believe I was and am wrong, but I would love to "hear" that for myself. Second, I bought a $900 pair of used Revel F36 tower speakers and was blown away by how much better they were at recreating music in my living room that sounded real (see this thread for more
Mind Blown).
So now to your question. At first I just was curious what others here thought was the PODR at which there would be no further meaningful and audible sound improvement from spending more money, but now that I have seen how dramatic a change there was going from Klipsch RP-280Fs to Revel Concerta2 F36s, I'm curious to test speakers in a much higher price bracket to see if I can hear any difference because given what I think I understand about speaker data I see it as highly unlikely that I will hear a difference given how flat the ON AXIS graph is for a F36. I think it probably represents quality sound reproduction high enough that I will not hear any difference in sound. At least that's how I interpret the graphs I'm looking at.
Importantly as I have mentioned before in other threads this for me has become an academic interest. I'm not trying to improve my home theater and I never ever ever listen to music on my system. I did so recently just because I believe it is the best way for me to test sound quality in my living room. So at this point I'd like to find a pair of tower speakers in the $5-6k range to see if I can hear a difference from my Revel F36s, not because I want to improve my listening at home, but just to see if I agree with the majority that one DOES have to spend more than $1k to get the best sound. Currently I'm leaning towards
Ascend Acoustics ELX Ribbon towers as being worth a try.
Here's an example of a data comparison that to me says I will hear no difference. The Revel F36 graph is just as flat as the Salon graph. I assume that means that the F36 recreates a song with the same accuracy as the Salon the only difference would be how loud one gets and how wide the dispersion is, but aside from that I would expect the sound to be identical for me sitting in the MLP with a "normal" volume. Anyways, I'm curious as heck to find out for myself. Of course, none of this should matter to anyone other than me as my personal ability to hear and my situation overall are obviously unique to me, but I most definitely am enjoying how much I'm learning from this discussion.