Well, part of the problem is that your test didn't really show anything. We all know that mathematical differences occur between mp3 and FLAC and that the FLAC file will be superior in terms of quality since it is lossless. Your test showed that. Your test did not give us anything about the perceived quality of the mp3 files though. There are mathematical differences but are these differences heard?
On top of that, you make many blatant claims (I can hear more than others) which really aren't needed and don't add to the strength of your test. If you can hear more than others (you even comment about audio clarity in a certain frequency spectrum) then why not back it up with a real audio test?
That is all we are trying to get at. The claims made at hydrogenaudio are valid in that you didn't show anything other than there is a mathematical difference between FLAC and mp3. We already knew this and we already knew that the mp3 format cuts frequencies off. The main point is if you can hear the differences. I can give you two red apples with one weighing in a little bit more than another one. Hence, they have a mathematical difference. However, do they taste different? No they don't.
That is the kind of test to make real claims about audio quality. You have to setup a blind ABX test. It would have been interesting if you did your original test then conducted a blind ABX test. Then you could have shown with your plots that there is a mathematical difference and that you can actually hear a difference as well.
As I said earlier, many people have run a 64kbps HE-AAC file through the same procedure and it cuts off frequencies way below that of a normal mp3. However, they then conducted blind ABX tests and have found it to be quite nice in terms of audio quality.
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