I'm no closer to understanding how audio grade fuses work but I got my new Hifi Tuning fuses earlier today for my amps and DAC. I installed the fuse in my DAC. The change in sound was immediate and apparent. Deeper 3D imaging. A little more clarity and crispness. Images have an even more defined body to them. And this is listening in the middle of the day, in the heat with the A/C running. Can't wait until tonight to see how it sounds. This audio hobby is just like a drug addiction- always looking for the next big fix.
Now the other part of this story is a sad and tragic tale. A tale of woe. A costly and tragic tale of woe. I ordered two fast blo Hifi Tuning fuses for my mono bloc amps. I originally intended to test the fuses in the amps first and then in a day or two try the other fuse in the DAC. But alas, ignorance can be costly. My amps require slo blo fuses. When I pulled them out to check the ratings I saw a single filament in the fuse tube and assumed fast blo. All I had to do was 1) Look on the back of the amp where it said slo blo or 2) Know and understand that the letter "T" on the end of the fuse stands for slo blo. And so my amps powered up with the new fuses for just the briefest of moments and then poof. The fuses are toast. An expensive lesson but now I know; and a word of wisdom for others who read these woeful words. (Good thing I didn't start out with those $400 brands). These Hifi Tuning fuses are much less than $100 right now on sale. It still hurts.
After hearing the change the new fuse made to the DAC, I mustered up some intestinal fortitude and reordered the proper fuses, this time for my Amps.
But now I have a couple of audio grade fuses to cut open and see what's inside for myself. It's either that or try to sell them on eBay as used fuses. Any takers? :)