fuses - the $39 ones or the 85 cent ones

I have to agree with Dave_b, the sonic benefits of these fuses change and improve over time. But I had what seems to be a unique experience after replacing blown stock fuses in my integrated amp with the HiFi Tuning fuses. The sound characteristics changed considerably and somewhat erratically, and it wasn't until many hours (>>100 hrs) that the sound stabilized and I noticed the overall benefits typically identified by users here and in professional reviews immediately after replacement. I am very pleased with the overall improvement in sound quality I am enjoying now.

My experience is described in detail here:

http://forum.audiogon.com/cgi-bin/fr.pl?ymisc&1192881548&openusid&zzKnownothing&4&5#Knownothing

Knownothing, since you do hear the difference, it would be interesting to see if you could hear the same level of improvement with the $12 Acme. No DBT, just listening.

When I bought most of my IsoCleans they were $25 each. They are now$35 for all values.

Supply and Demand will get you every time!

Nsgarch, you should also take a look at
http://www.cryo-parts.com/fuses.html

Ceramic and cryo'd for $7.75 - no indication of sand-filled, but I have sent them a note. Now these prices are more like it (though I don't know if they are better, the same, or worse than Isolclean/HiFi Tuning ones).

Now if I can get a cryo'd, ceramic, sand-filled fuse for $7.75 I'll try them. If the Isoclean/HFT can make a difference, these must also, but for a lot less money. I'm going to try the HFT Acme and the ones from CryoParts with my Atma-sphere electronics and Merlin VSMs (both pretty resolving). Now if I can't hear a difference, it only means I can't hear a difference; which does not prove much - it could mean I'm deaf or my system stinks. But if I do hear a difference there likely is one. Disclaimer, I have not financial interest in any of the vendors or providing cryogenic services.