fuses - the $39 ones or the 85 cent ones

By the way, if I am mistaken as to the location of the fuse of which you speak, and it is indeed neither a line fuse nor, for that matter, a fuse for one of the rails, then it makes perfect sense that the gold endcaps would make a difference. I was just not aware that any amplifiers used fuses to protect a differential input stage. I would highly suggest that you replace both of the fuses at the same time and purchase only a matched pair.

Musicnoise, your theory does not apply here in highend audio.
The only explanation is what you hear with your own ears!!
Whether it can be explained scientifically, mathematically or otherwise means nothing if you can't hear a difference with your own ears. The proof of science cannot change my hearing!! or what I percieve I hear.

Undertow, I wasn't aware that Krell went out of business. Where did you get this information?

I tried some of the premium fuses in my Accustic Arts transport and DAC (not tried them in pres or amps) and I cannot tell the difference, but I'm 50; maybe one needs to be younger. All the same, they seem well made as far as fuses are concerned, but I'll be sticking to sand filled ceramic types from Roger Modjeski, not that I can hear a difference, but for $3 I don't care (as much).

Audphile1
a couple months ago there was an article and a couple of threads on Krell finally going out... They might be still operational, I don't know, maybe somebody saved them with a checkbook, again I don't know.

Musicnoise
Gold end caps have nothing to do with it, it is the better element and vibration control inside not limiting the current or something like that which matters in this case I would assume...