Synergistic Red Fuse ...

Charles,
You have a very nice setup, all Coincident equipment is major bang for the buck.
The Carissa is modded to some degree, Coincident stock. The Coincident is higher resolution and more dynamic, tonality in my setup spot on, great amp. I've thought about changing out the coupling caps in the Coincident to Jupiter, which I did in Carissa, but things are too nice as is. I'm not even sure I heard that much improvement with the SR fuses in, but then they never lasted long enough to properly ascertain.  I only use the Turbo in direct mode (bypassing input switching and volume pot), coloration and some loss of transparency using as preamp.
I'm also in the midst of trying a variety of fuses in Turbo. The Radio Shack 6.3a are robust and have good sound quality, prefer them to other generic glass bodied fuses (6.3a is the stock value, and what came with amp). I tried the Schurter SMD-SPT's as well, the 6.3a has blown after a number of start ups. The 8a has yet to blow. I prefer the Radio Shack to these, Schurter has a flatter, more recessed soundstage, perhaps a touch more rolled off on top. Today I'm going to try AMR 8a. I also have some Bussman ceramic bodied, some generic ceramic bodied and other generic glass bodied to try. At this point I've given up using the SR fuses in the Turbo and Carissa. The large reservoir capacitors in 845 power supplies require too much current for too long , the SR fuses can't handle it. I would like to hear of someone successfully using boutique fuses in a 845 amp.  A soft start circuit would likely solve this problem, but perhaps negatively affect sound quality (the old straight wire issue).

I’m highly tempted to try the Black fuses now that they’re $85 each but am a little reluctant because the Red fuses did nothing on my Magnepan 1.7i’s.

Limniscate,
Some listeners don’t hear any(or little) difference with the premium fuses. The Reds were beneficial in my case and the Blacks were noticeably better. If you find that their effect is minimal just return them for a refund. What’s works for me may not do the same for you.

Sns,
Thank you for your reply. I use the Jupiter Copper foil capacitors (input coupling stage) in my Frankenstein amplifier and I am happy with them. They are not a dramatic (night/day) transformation but certainly improved the sound enough to make the effort worthwhile. I imagine that they’d have similar impact with your Turbo amplifier.
Different application but I got a more significant change with the Duelund CAST capacitors placed in my DAC  (output coupling site) and in my speaker's crossover at the tweeter. 
Charles 

Okay guys, I need some help in understanding what SR Black fuses to order this round. First, an admission and then a question.

The admission: I posted earlier in this thread that I had two SR 1A small Black FAST fuses blow in my Ayre K-1xe’s external power supply when plugging in the power cord. After re-inspecting the stock fuse I realized that the marking nomenclature had a "T" at the beginning, as in "T1L250V". Not knowing what that meant initially, I simply looked at the filament and saw that it was thin with no windings around it (like the higher value SLO BLO fuses I had around) and ASSUMED that the original fuse was FAST blow. After doing some research, I learned that the "T" means "Timed" and therefore SLO BLO. That probably explains my problems with the FAST BLO fusing blowing. A pretty expensive mistake. Doh!

The question. I am ready to order SR Black fuses for my REL subs. The "power fuse" is a small GLASS fuse that has this marking: "T5AL250", so I should order the SR SLO BLO 5 amp fuse.
Now for the twister: The RELs each have two SMALL rail fuses on the circuit board inside the cabinet that have WHITE BODIES (CERAMIC?) with markings "T6.3 AH 250V". Research online gives mixed opinions as to the advisability of replacing a ceramic fuse with a glass one. Bottom line: is it okay to use SR Black fuses of the same rating to replace the stock CERAMIC ones in the RELs?

Best to you all,
Dave

Hi Dave,

I believe that the main difference between a ceramic fuse and a comparable glass fuse is usually in what is called "breaking capacity." That refers to the maximum amount of current the fuse is rated to be able to safely interrupt when a fault requires it to blow, that would not result in it rupturing or exploding or failing to open the circuit. And I believe that ceramic fuses tend to have much higher breaking capacities than glass fuses that are otherwise similar.

So that difference would only come into play if a fault arises in the sub which requires the fuse to blow. But whether or not the breaking capacity of the SR glass fuse would be adequate in that event can't be predicted with any kind of certainty without knowing the details of the sub's circuit design, and without having detailed specifications on the SR fuse. FWIW, though, my guess, based just on instinct, is that it is unlikely that you would ever have a problem as a result of that difference.

A separate question, though, is whether it would be advisable to choose an SR fuse having a somewhat higher current rating than the stock fuse, to minimize the likelihood of the false blows that various people have reported in this thread. My guess, again based just on instinct, is that it would probably be a good idea to go up one rating increment, which if I recall correctly would be to 8 amps.

Good luck. Best regards,
-- Al