Hi, I have tried very hard too, but I can't either. I think iTunes + is really good. I have devised an online blind test to specifically compare CD vs iTunes plus (Lossless vs. Lossy | Can your ears tell the difference?). You might want to take a look. Of the 50 or so people that have taken the test, only one has been able to consistently prove that he can tell the difference (he did it for clips #3 and #6). Try the test and let me know what you think. I also have a post where I null test mp3 and AAC vs CD. The results are interesting.
