What are you listening with? There can be a whole bunch of things causing the brightness..
Yeah, I have been doing this longer than most have been alive. Here we go;
Yggdrasil
Freya
Stasis Mdl. 2, Hexfreds in P.S., new resistors throughout, mostly Resistas a couple of Holcos, Black Gates on drivers cards, Mills bias resistors on o/p transistors, then send to Threhold's former lead technician for matched output devices, newer tighter tollerances, and new PS caps, higher capacitance, oh, used different values on bias resistors to increase power output. Jon Solderberg, Threshold tech, said it's the best sounding Stasis amp he's ever heard. He began using Black Gates in his mods after that till they went out of business. Then I also have a highly modified Sony DVP S9000ES which is not bright. That all feeds B&W 801M Series II's with modified crossovers, protection ckts disabled and Audyn Copper Max caps bypassing any caps in line with drivers. I may have replaced resistors in line will mills, but I would have to check to be sure, it is my M.O. though. From Freya to amp I have used multiple ICs, currently I have I believe Silver Sonics, or silver something's which have never been bright. Then Goertz MI3's to woofers, MI2 Pythons to mids and tweeter, returns shorted and 10 ohm mills resistors between hots. That is about it.
I can make the Sony bright with the right opamps, I have a ton to choose from. If someone said X op-amp sounds good I have probably had it in my DVP output at one time or another.
FYI, aside from a ton of Black Gates and V-caps in the O/P, I have Sonic Imagery Labs 994Enh-Ticha Dual OpAmp DIP8's in the I/V stage and LM4562's as drivers in the Sony right now.
I also have KEF 105.2 Reference speakers, Paradigm Studio 100 V 2's, Ellis Audio 1801's some obscure JH3'3, and a pair of Acoustat Mdl. 3's at a friend's house, but I pretty much use the B&W's exclusively.
No, it would not. But if you believe yours sounds better with the fuse one way than the other I highly recommend you use it the way it sound best to you. Electrically it makes no difference.
Personal preference, happy listening and all...
Theoretically a fuse can degrade over time. Other than either starving equipment for power, or a power cord being woven to act as a choke in an area where much noise is induced into the power line from the transformer to the home, OR something like a dimmer is in play in a home, I don't generally buy into a 5 or 6 foot cable transforming things, much less a fuse, but I have been proven wrong too many times to argue. It seems completely implausible to me that there is directionality in a fuse, but at one time I also believed an electrolytic capacitor was an electrolytic capacitor, only after I heard a difference did I believe it and going in a disbelieve, I don't think that I just imagined it, and if I did it's a pretty massive hallucination because I have yet to meet anyone who hasn't been able to hear a difference.
Not better. Totally different. Better is in the ear of the beholder.
Electrically it makes no difference according to the criteria used in manufacturing OEM fuses.
Just like two different brands of 12AX& tubes are electrically the same. But?
Except the 12AX7'S are in the audio path. For anything in the AC circuit to effect the DC circuit you would have to be having real issues beyond the ability of the DC circuit's filtering's capability. Even then, it will almost exclusively show up in the high frequencies as noise and have virtually no impact on low frequencies. Low frequency issues dealing with power generally relate to insufficient current, and I seriously doubt that we would see a difference in the milliamp draw based upon fuse orientation. I could be wrong, but I would be amazed if I were.