He told me that he did, in fact, hear clear differences in power amplifiers, but that he did not value the differences as significant in the context of an audio system.
This is a point that I and others have brought up before in similar threads. I truly believe that a lot of objectivists who argue here can hear the differences that others do and simply dismiss them as insignificant.
The underlying reasons are not important. What is, is that they are dealing in bad faith.
All the best,
Nonoise