What are fuses used for?


I have, I’m sure to many, a very dumb question. I keep reading about fuses.  I have a fairly sophisticated system and have never come across the need for a fuse.
Can someone tell me where these fuses go and what they’re used for?
128x128rvpiano
erik_squires4,257 posts11-23-2018 8:12pmI’m definitely not about to take work assigned by you, George.

I was merely pointing out that if audiophile fuses do anything at all the effects would be super easy to measure at the fuse itself.

>>>>Isn’t it nice to think so, Eric? The name is Geoff, by the way, not George. It’s probably best if you don’t do the test after all. 😀
I second wolf's response

I recently tried some SR Blues in my system.  The company I purchased from was out of stock on a couple, my system requires 6.  I installed in the preamp and the phono preamp.  I REALLY wanted to hear a difference as the salesman had me so excited.  He assured that this would not be one of those experiences where you are struggling to hear a difference....it would be jaw-dropping.  Well, I thought it sounded better but was not jaw-dropping.  I listened to for about a week.  Still no update on the backorder fuses, so I put in 1 of 2 in each of my ARC mono block amps.  I turned them on and one fuse popped.  I asked the sales guy and he said that cheap fuses are built with a wide variance in their actual ratings.  The SR are so closely built that my amp likely was drifting above that rating and my stock fuses covered it where the SR didn't.  Oooookaaayyyy
So now I asked him, well if that's the case why didn't we up the rating on all 6 fuses?  He said we could have done that, but no worries.  I said well this is quite frustrating and concerning to me and now I AM gonna worry about the other fuses popping.  If this happens after my trial period then I'm subject to changing $150 fuses if they pop.
I went ahead and switched all the fuses back to stock and actually felt the sound improved.  This told me that my emotions were dictating what I heard.  
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