fuses - the $39 ones or the 85 cent ones

Pubul57 says:

"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."

I dunno, didn't try them? Cheap is good, especially if its really good :-) Changing fuses is enough of a hassle that I am not likely to mess with a good thing for now, but if I get the hankering to fiddle with fuses in other pieces of gear I might give some of the cheaper alternatives a shot.

For what it is worth, the three HiFi Tuning fuses I replaced in my integrated amp taken together cost about the same as the AQ diamondback interconnects I am currently using, and the change made about the same degree of improvement in the sound quality as when I swapped the AQs in for some relatively cheap Monster cables.

Its hard to tell what my favorite tweak has been, because each improvement allows me to discern a greater degree of difference in sound resulting from the next action!?! Adding these fuses has to be way up near the top...

I just cracked open a Buss Fuses ceramic fuse. The fuse is a sand-filled ceramic tube. I'm using these ceramic fuses on my Maggies 3.6R. The fuses are mounted on the speaker frame, so they are susceptible to vibration from the drivers. There is one fuse for the mid-range driver and one for the ribbon tweeter.

For the ones who joined the discussion in the last few days, I recently compared four fuses, two glass and two ceramic, including the HiFi-Tunning fuse. The sound was a lot cleaner with the ceramic fuses than it was with the glass fuses. Of the two ceramic fuses I tried, the Buss ceramic fuse provides a cleaner, more balanced sound. There is more energy and definition on the upper-base, lower mid-range region. The highs also have more clarity and definition. The HiFi-Tuning fuses were almost as good as the Buss fuses, but the latter has a much cleaner presentation.

It seems to me that the sand-filled ceramic tube absorbs vibrations quite well, hence contributing to the cleaner sound. Also, the filament gets thicker in the middle http://cgim.audiogon.com/i/vs/i/f/1220802079.jpg

I purchased the Buss ceramic fuses from: http://www.mcmaster.com/

The fuses are under the "Lighting and Electrical" section and cost $6.06 for a pack of 5. They are UL listed.

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!
.

Nsgarch

BTW, were both of the ceramic fuses you tried sand-filled?

I don't know if the HiFi-Tuning fuse is sand-filled. Perhaps others know the answer to that question.

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.

I have observed this as well when auditioning cables. For instance, I think one of the reasons that the Nordost flatline series of cables "lean" toward the upper registers is that they are more prone to vibrations than other cables where vibration control has been part of the design requirements.

In the case of my fuse comparisons, the difference between the glass and ceramic fuses was quite pronounced. I think that the ceramic body + sand-filling + the little "bubble", if you will, on the filament, help to explain why the sound is cleaner with the Buss fuse in particular.

I should also mention that on the Maggies 3.6R, the fuses are easily accessible and can be changed in seconds without powering off anything. Of course, I made sure there was nothing playing.

One factor to take into account when trying fuses on a power amp or preamp is that, for safety reasons, the unit has to be powered off. Depending on the design and topology, the unit may need some time to fully perform at its best again. IMO, this can be an obstacle when doing A/B comparisons because there is always going to be a longer time delay between tries. Therefore, one may be hearing the difference between a "warm" and "cold" unit, as well as the difference between fuses.

Isanchez, are your Bussman's MDAs? I got some, and they have no sand in them.