That graph posted by cottcott44 on the first page of this thread is very interesting.



From the graph, you can see that MP3s at 160kbps and above do not give you signal loss until you are over 16 KHz.

Many people cannot hear anything above 16 KHz so they cannot tell the difference between WAV and MP3 at rates of 160 kbps and higher.

For people who cannot hear above 14 KHz, and there are many, note that even a 128 kbps MP3 covers up to 14 KHz without much loss, so that explains why for casual listening even 128 kbps sounds OK to a lot of people.

There are a few people who can hear at 20 KHz, so they might be able to notice differences with high bitrate MP3s, but if you're in a noisy club with a hundred people talking and you have the big bass drum sound, I doubt that the 20 KHz sound makes any difference at all. And most music has very little sound at frequencies like 20 KHz, in the sample graph the 20 KHz level is over 50 db lower than the bass level.