Similar to @mapman I tried a SR Blue fuse in an integrated tube amp a year or two ago. It did no harm to the sound but I can't say I heard an improvement. I kept the fuse (they do offer a generous return policy) thinking someday perhaps I will move it into a different component (as perhaps it will make a difference there? - I'm very open minded), but I don't think I'd buy another unless it proves to make a material difference in a future component.
I can hear the differences that is made in cabling, use of cable risers, and even HFTs but as much as I strained I just couldn't hear the fuse difference. I would not be shocked if it works in some systems or with some components but didn't make a lick of difference in mine.
I can hear the differences that is made in cabling, use of cable risers, and even HFTs but as much as I strained I just couldn't hear the fuse difference. I would not be shocked if it works in some systems or with some components but didn't make a lick of difference in mine.