In my case new fuses cleaned the sound (grain on highs), improved bass and impulse response (tighter and deeper bass, faster impulse) and finally better separation - mainly when two or more tones are playing at the same time i was able to better distinguish each one)
I have started with hifi tuning supremes few years back, then briefly tried AHP (only in DAC) , but ended with Audio Magic Beeswax - most expensive, but this was again clear improvement over hifituning supremes.
Important remarks:
- overall impact on sound in my system was like 5-10%
- you need to have resolving system to appreciate fuse change
- these audio fuses are actually directive and one must try both directions to find out best for his scenario
Also i have recently replaced standard breaker for fuse box with 16A beeswax fuse - this made again nice improvement, mainly in bass+midbass tightness and dynamics , but also other attributes i’ve described above, just with smaller impact. I need to note that whole audio chain is powered by P10.