I think the differences are usually smaller than what people over here state, I have quite some friends who cant hear any difference whatsoever. for me, I think it really depends... I still struggle to tell the difference between the 2 filters on my ibasso dx100 myself in all honesty. It seems like sometimes I don't hear any difference, actually most of the time. and sometimes it feels like the slow roll off filter is slightly louder or has slightly more treble extension than the fast roll off. it can be possible that I don't hear any difference at all and its just all placebo especially when its lee730 who told me the slow roll off has more treble extension so i start to think that way. sometimes some differences are much bigger, like my ultimate ears trifi10 has more bass than my etymotic research hf5. that's pretty obvious. however, that's more sound signature than quality. i also notice a bigger jump from quality comparing something like my etymotic research hf5 (my first quality audio gear) to a 10 bucks iem than say a 100 bucks headphone to a several hundred bucks headphone. it also depends on the track as well. maybe an easier way to distinguish the sound difference is to dissect it into different categories, like comparing the 2 headphones by bass first, then mid, then treble. differences in bass and mid are also more easily distinguishable to me, my theory is either im not a treble listener like i don't usually actively listen for treble or my music simply does not have a lot of treble. i would guess its both with the first option being the more major one. i think it also depends on my mood. sometimes i hear absolutely no difference at all when im switching gears but sometimes i notice a lot more. i also think i can train my ears if i practice more. i also have an expectation that the higher priced or the more respected gear should perform better. i want to get rid of that feeling because it can cause bias. it can go both ways with this, i can expect more so i automatically imagine the higher priced/more respected gear to sound better when it really isn't or expect a huge jump in sound quality when the difference is not as much and come away disappointed and judge the higher price/more respected gear harshly and the cheaper/less respected gear a lot more favorably than i should.