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
@zavato
I can’t answer your questions. But I hope you get to hear the Black Fuses in your transport one day. I would love to hear your feedback. It really has made digital so much better...not a subtle improvement.
I was always of the mind that a better made fuse would perform better. My own ears proved it. What I didn't have was my feet planted on the side of the argument that they are directional. That was almost two years ago.

Fast forward to just last week, I've been considering getting new speakers because the highs were never as good as what I had before. Just for sh*ts & grins I opened up my SACD player and changed fuse directions on all four fuses (some were in the signal path) and lo! 😃

Everything improved. I'm keeping my speakers for the foreseeable future. Yes, fuses are directional. Maybe not in the AC path but definitely in the signal path. Others might have been lucky enough to have put them in right the first time as it's a 50/50 shot. I wasn't.

Now I'm thinking about those SR Black fuses. Damn.

All the best,
Nonoise

gdnrbob
Oh, your are going to light fires, especially with that avatar ;)

Re: directional fuses, I recall Ralph at Atma-Sphere mentioning something, but I forgot the details. Though I think he said there was something to it. (If I am wrong Ralph, sorry).
B

I don’t want to put words in Ralph’s mouth, either, but I’m pretty sure he’s not really on board the whole fuse directionality train. His argument is (and I suppose he could possibly be accused of fence sitting on fuse directionality) that when someone flips the fuse it somehow magically gets a better grip in the fuse holder. Cough, cough  As I recall the other fence sitter Almarg agrees with Ralph in this regard. 

Geoff’s statement above is correct. See the first of my posts dated 10-28-2016 in the long running "Synergistic Red Fuse" thread, in which I quote posts that have been made here by Ralph and several other designers of well regarded audio electronics on the subject of fuse directionality. I quoted Ralph’s comment (which had originally appeared in another fuse-related thread) as follows:

Ralph Karsten of Atma-Sphere:

… Fuses are inherently incapable of having directionality in any way whatsoever.

… I joined this thread recently with some results on testing. Those results are that the directionality appears out of coincidence and that actually greater improvement can be had by rotating the fuse in the holder for best contact…. Reversal is improving the contact area because fuse and holder are not dimensionally perfect and the fuse might sit better in the holder in one direction. By rotating the fuse in the holder without reversing it gets the same effect only more profoundly.

Also, in the numerous fuse-related threads that have appeared here over the years I can recall exactly two members who have reported experimenting with fuse rotation: Ralph, and a member named SGordon1, who posted in the Red Fuse thread on 5-3-2016 about having done that. Both gentlemen reported that significant differences resulted.

Also, as far as I can recall none of the many people who have reported hearing differences as a result of reversing the direction of a fuse have ever indicated that they went back and forth between the two directions multiple times, reinserting the fuse each time with randomly varying rotational orientation, to verify that their results were repeatable and that they were unrelated to rotational orientation.

Now, does it seem unlikely that rotating a fuse in its holder would have a reasonable likelihood of making an audibly significant difference? In the absence of empirical evidence, such as Ralph has provided, my technically-based instinct would be to consider it as being unlikely although possible. However, I would think it to be vastly more unlikely, and in fact impossible, for a fuse to have **inherent** directional characteristics, to an audibly significant degree. And as I mentioned, several other designers of respected audio electronics whom I quoted in the post I referred to above agree with me.

Regards,
-- Al

Al, thanks- I had seen the thread you linked to but only glanced at it.

Are any of these aftermarket fuses UL listed and do any manufacturers install these in their gear straight from the factory?