What a long thread ! But not as bad as cable argument threads.
I just tried a Synergistic Black fuse in the custom power supply for a MAC Mini. The P.S. is made by Mojo Audio, the fuse is 2 amp slo-blo.
I gave the Black fuse about 3 days inside the unit, with two on off cycles. Compared it to an AMR fuse and the stock non audiophile fuse.
The AMR was worse sounding than the stock fuse, and the Black is better sounding. In what ways ?
The AMR was too murky sounding, not as clear and vivid as the other two. This fuse only sounds good in one of my components, but does the murky thing, or roll-off in other components.
The Black fuse relieves some brightness and glare that the stock fuse has, otherwise the stock fuse is pretty good.
I got curious about the Black fuse after trying a Synergistic Atmosphere 1 cord on this MAC Mini power supply. It bettered about five other cords I have here.
I'm not about to rush out and buy more Black fuses, but now I know what they do. Hopefully the profit made by Synergistic Research from these fuses will go to R&D and good pay to the employees.