Do Fuses make a difference ib sound?

Not sure. Bought used SR orange for all my components. They are very reasonably priced used, so a low cost tweak. As with other low cost tweaks, if they improve things… great… but don’t A/B. As @mitch2 said, they certainly don’t sound worse. 

Unwise to monkey with stock fuses as a layperson. Wyred4Sound offers fuse upgrades in their upgrade options on the STP SE. Connectors are cheaply built so multiple fuse r/r may loosen up the contacts. Or if you spend enough for nice boards with nice components the fuse will be selected by the engineers. Fuses are safety devices. 

If the sound is affected by .5" of wire in the power lead the designer of the power supply is incompetent.

@xmbw4 how do you know @jhnnrrs hasn't tried them?

I have, and I tend to agree so based on my personal experience with a few fuses and cables from SR, I will not buy anything else from them.

Of course YMMV.  

@chiefsteward1 IMO no, but why not try them from The Cable Co. as suggested if you really want to find out.

Personally I'm done chasing tweaks that promise instant gratification (or require 100's of hours of break in time - oh crap, the return window closed).

Right now all my resources are focused on acoustics. I'm shocked at how many measurable issues I have with the space, with a system that sounds pretty darn good to me as is.