I am surprised that this is not generally accepted. My experience is that most good solid state amplifiers which are operated well within their capability (no clipping - i.e. at very modest levels) do sound quite close to eachother - much closer than different speakers. I for one would not be confident enough to pass a test unless it was with a test signal. I don't mean to say amps do not have their flavors - they do but it is definitely, for the most part, what I would call subtle.
In that sense, Richard's test proves nothing to me.
Of course, there are lots of very good reasons to own a high quality amplifier...good music is dynamic, extremely dynamic and it is at those extremes that great amplifiers can and do make a HUGE difference (low and high output levels)...if you want percussion or large band orchestral done well at realistic levels without sounding horrible and harsh then the highest quality amp makes ALL the difference.
In that sense, Richard's test proves nothing to me.
Of course, there are lots of very good reasons to own a high quality amplifier...good music is dynamic, extremely dynamic and it is at those extremes that great amplifiers can and do make a HUGE difference (low and high output levels)...if you want percussion or large band orchestral done well at realistic levels without sounding horrible and harsh then the highest quality amp makes ALL the difference.