fuses - the $39 ones or the 85 cent ones

(Assuming) the fuse isn't in the signalpath, and if it's the correct rating as specified by the OEM, then the equipment sees the same power quality as with any other fuse of the same rating. Sonic differences you hear are the result of otological axons in your brain losing their myelin insulation (due to age, stress, diet, genetics, etc) and lying too close to other axons carrying intense signals of unrealized desire to the hypothalmus (wishful thinking.)

". . . .and the Doctor said, 'them crazy dreams are only in your head!'"
-- B. Dylan
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Rogermod's ideas make thermodynamic sense, so I might try those.

Dave, can I assume you had used Pro Gold on the 'regular' fuses too?

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Here is my email exchange w/ Acme:

Are your your silver/ceramic fuses 'typical' in their physical design: i.e. a fine wire passing through a ceramic tube? I ask because one of the 'devils' in filament fuses is vibration of the filament. Some designs now have the filament completely embedded in the ceramic or other material to damp vibration, and I wondered if yours are like that?

Hello Neil,
The filament is not embedded but is in a very close tolerance tunnel.
Michael

So I still like Roger's sand-filled fuse the best. Unfortunately he only has them in values he uses for his equipment. But these silver cryoed Acmes are starting to sound like a cost effective solution -- especially if one feels (as I do) that the important properties are vibration damping and heat dissipation --- not the use of exotic metals.
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Pubul57, thanks for the lead. Starting with that, I eventually found this US company, sand-filled ceramic, fast and slo blo, all sizes, UL approved. I'm going to try some!http://okwelec.com/products/camden/fuses/ceramic-fuse.htm

Isanchez -- thanks for such a complete report - yes, you were using your own ears, but this was a comparative exercise to begin with. And thanks for comfirming (my for now mere speculation) that vibration might be the main problem (I hold nothing against gold or silver filaments ;-) BTW, were both of the ceramic fuses you tried sand-filled?

The reason for my interest in mechanically isolating conductors is I've have been working with Purist cables for some time now (including a pair of their new, solid core Provectus speaker cables, Albert Porter kindly lent me to audition.) And I am absolutely convinced that a properly chosen shock-absorbing material around the conductors is essential to achieving the "blackest" possible background in the final sonics.

So it comes as no surprise that something like a hair-thin fuse filament hard-mounted in a chassis (and usually not far from the power transformer!) would sing like a bird.
I wouldn't be at all surprised that the exotic filament metals in the expensive brands might vibrate less than nickle/steel, but for thirty-nine bucks, they could throw in a little silica sand too!
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Dvrs -- some manufacturers are doing that -- such as Dan Wright of Modwright who posted some comments here.

I suppose the next step will be radioactive fuses.

as your amp disappears in a small mushroom cloud!
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