John K: What you said makes sense to me ("On music, testing has shown that THD has to be higher than 1%(sometimes 2-3%) before a difference is identified in blind tests. There's no way that distortions so far below the threshhold of audibility as .04% and .08% could be differentiated."). I haven't A/B'ed anything, so was just wondering.

Are those tests on the Web anywhere?

"These go to eleven."