fuses - the $39 ones or the 85 cent ones

I will probably try some in my amps with tubes. Shucks, I might get more enjoyment from them than the same priced 2.5 bottles of wine.....

Tvad, actually, none of the fuses I tried show up in the UL database when I do a search.

The fuses themselves have engraved the certification logos. My eyes are not that good anymore, so I had to use a magnifying glass to make up some of the logos.

OK, I went back and forth replacing my old stock fuses in my 400xi vs the Hi Fi Tuning fuses plus I checked for directionality of the Hi Fi fuses and the results are....drum roll please............Hi Fi Tuning Fuses are directional (arrows should point toward the component) and sound far superior to the stock fuses. Having the fuses in backwards causes the highs to become shrill, forward and hard sounding, bass lacks focus and instruments seem a bit out of sync in relationship to each other. The stock fuses are less dynamic, less transparent, do not image as well and seem to add a bit more distortion. Bottom line is that the Hi Fi Tuning Fuses open things up more, seperate instruments better, increase dynamics, and reduce distortion...quite a bargain for chump change:)

So Dave, are you saying the change was dramatic?