Fuses fuses fuses


Ok, this is about fuses

1- a standard Bussman fuse is UL approved. Are any "high end" fuses UL approved?

2- do any component manufacturers supply their gear with any of the usual suspects of high end fuses as opposed to a standard Bussman?

3- let's say fuses do make a difference. Given incoming power is AC, why could fuses be directional? 

Not meaning to light any fires here- 

thanks in advance 
128x128zavato
First, to be sure it’s clear, the point of contention in this thread does not concern the efficacy of fuse upgrades. It concerns the OP’s question no. 3, regarding fuse directionality. And in that regard there appears to be a reasonably compelling body of anecdotal evidence, especially in the long-running Synergistic Red Fuse thread, that changing the direction of a fuse can make a difference, even if it is an AC mains fuse.

However, the problem is that establishing that changing the direction of a fuse makes a difference does not establish that a fuse is inherently directional, as many seem to automatically assume. One does not necessarily follow from the other, especially given Ralph’s empirical findings that I cited above (which he reported to be both measurable and audible), and also given that in the opinion of many of those having an extensive background in electronic design there is no means by which that is possible. As I put it in my post in the Synergistic Red Fuse thread that I referred to earlier:
[Inherent directionality in fuses] is fundamentally irreconcilable with any reasonable understanding of how electronic circuits work. Which is not to say, of course, that an understanding of how electronic circuits work can explain or predict everything about what we hear or don’t hear from our systems. It certainly can’t. But it can often help to provide a perspective on what does or does not have a reasonable possibility of being audibly significant.... And again, none of this is to say that I doubt the accuracy of most of the reported perceptions, it just means that in cases where those perceptions are accurate I believe that the cause was something else.
When the direction of a fuse is reversed all of the following variables, or at least potential variables, are being changed simultaneously:

1)Contact area.
2)Contact pressure.
3)Contact resistance.
4)Oxidation between the mating surfaces.
5)Warm-up state of the equipment.
6)Contents of "volatile" digital memory elements that may be present in the design (i.e., memory elements that don’t retain information when power is removed).
7)The states of other circuitry that may undergo re-initialization at turn-on.
8)Probably other variables that I haven’t thought of.
9)The direction of the element in the fuse.

In order to conclude and legitimately be able to claim that no. 9 is responsible for the difference that is heard, given especially what I and four different experienced designers of well regarded audio electronics have said in posts here which **strongly** point away from that possibility (again, see my post dated 10-28-2016 in the Synergistic Red Fuse thread), at the very least it is necessary to reverse and re-reverse the fuse multiple times, reinserting it each time with varying rotational orientation. To verify that the perceived difference is repeatable, and that it is not due to the phenomenon Ralph has reported, or to other variables.

And as I and Davehrab both said earlier, it appears that no one posting in any of the various fuse-related threads here who has claimed to have found that fuses are directional has done that. Which is understandable, given that significant time and effort would be required to do so with reasonable thoroughness. What is not understandable, though, to me at least, is failure to recognize that any of the other variables I listed may be responsible.

Regards,
-- Al

Almarg, let me give you a little logic lesson if I can be so bold. Just because there are a lot of variables doesn’t mean that fuses are not directional. Capish? If you guys were really interested in the truth rather than arguing til you’re blue in the face you’d have done the experiment yourselves a long time ago. The other variables can be controlled. Like the placebo effect, whatever. Don’t you know that?

Note to self: Why do naysayers, the uber skeptics , the practitioners of uber careful pseudo logic always demand that believers must be the ones testing for fuse directionality? Why don’t naysayers test for themselves? Wouldn’t that be uh, more convincing for them? I mean, why would these uber skeptic’s even believe any test by a True Believer? It doesn’t make sense. Yet the demands for tests, especially the silly double blind ones. Give me a break! Tests are for sissies. My guess is the pseu-pseu-pseudo scientists don’t want to be found wrong and be the laughing stock of all the other self-appointed shepards of the pseudo audiophile flock. This whole anti fuse directionality movement is really a big nothing burger. 🍔
Geoff,

Don't waste your time or energy on these irrational people. It's typical of this generation to think they're right whether they tried things out for themselves or not. It's like my son-in-law who thinks everything he reads on the internet is gospel. I just sit back and watch him make a fool of himself. As the old saying goes 'experience is the best teacher'.
It is placebo effect IMHO, but there is nothing wrong with it - the result is what counts.  If it improves the sound, then why not?!  Trying to convince believers is wrong, as wrong would be to tell the truth to a person who gets headache relief from placebo pills.
A placebo effect wouldn't compel me to defeat the tone controls of my integrated to offset the now, too high treble boost. Nor would it extend the soundstage permanently, instead of occasionally, beyond my speakers. Nor would it alleviate the upper mid bass emphasis (which I thought was a permanent feature due to rear porting and close front wall placement). I could go on but the naysayers would write it off as a sort of delusion, which is pure and unadulterated crap. 

One of the main tenets of scientific study is that it is repeatable, by OTHERS. So, get off your butts and try it for yourself, and stop quoting the bits of "science" that gives you the warm and fuzzies but amounts to nothing more than another dose of "weak tea" reasoning.

All the best, really,
Nonoise