Here is the correct link
http://www.ultrasystem.com/usfeaturedprodsFUSE_LIT.html
I read it and I was interested that the fuse they sell was the one with the best measurements.
Also this is only for Slo Blow fuses right.
Hi Steve,
I am responding to you, but this is a general statement which covers things that you didn't address, so don't take it personally.
The only thing that makes sense to me is if the fuse has an internal circuit that filters the AC in some frequency range so that in some components it may cut down distortion that the components power supply isn't designed to handle.
Power supplies are generally made to filter 60Hz. If you have noise on your line from noisy power supplies, phone chargers, computers, TV sets, all use switching power supplies which are notoriously noisy, most component power supplies will not filter it, so it can reside on your DC supply to the components in your unit, which can then through lower frequency harmonics, muddy up your sound.
That's why I believe that some love different power cables, and many, once you get to 12 gage wires, here no differences in their system. Not to mention that some components are less than flat, and may themselves filter out the noise, negating the necessity for prior filtering.
If I remember correctly Spectral gear used to be able to amplify 1 to 100MHz, so I suspect that if Spectral preamps and amps didn't have nearly perfect power supplies they might be very susceptible to such noise.
As for directionality, if the fuse had an internal diode, or if itself acted as a diode, coated wires allegedly act as diodes, that would explain the directionally issue.
Having said all of this, I have never personally heard a difference in power cables, unless wires of sufficient gage were changed for heavier gage cords, and I have never bypassed or replaced fuses with boutique fuses. I am just looking at how electricity CAN or MAY be effected by such things.
One other factor is your speakers. Inefficient speakers, usually due to the crossovers, often don't pass low level details well. I have owned some highly reviewed, even by people I trust, but I was amazed when I went to a full range drivers how much detail my upgrade crossovers were burying.
So, if 2 people with identical systems have different results, there may be multiple reasons for that. One may not be battling noise the other doesn't have, one may not be listening as deeply as the other, they are not detail oriented, or like a friend of mine who loves bright, one may not have a full range of hearing.
I have ordered several lower dollar power cords just to tinker, but regardless of what I do or don't hear, I have been proven wrong about things audio that I will not say that someone is delusional because X did, or didn't do X, Y, or Z.