We can measure differences in amplitude as fine as .01 db at 40Khz. Can the
human ear hear this? Absolutely not. There are many other examples just
like this -- where we have the ability to measure differences that are far
below the threshold of audibility. So, Mr. Newell's "personal"
view, if unqualified, is simply incorrect. It is as valuable as my "
personal" view that the moon is made of green cheese.
But, let's not discount the importance of the human ear. Afterall, this is what
we use to appreciate audio. If the human brain and ear have the awesome
ability to distinguish a difference between the sound of copper and silver, you
should be able to produce at least one double-blind study where someone
has heard the difference between silver and copper when matched for
resistance. You will not be able to do this. No one has ever demonstrated
this awesome ability. Ever.