fuses - the $39 ones or the 85 cent ones


My Rogue Cronus recently blew a slow blow fuse. I was surfing to find a replacement. The stock fuse is a typical metal end cap, glass and "wire" fuse. The audio emporiums only seemed to offer these $39 German gold plated end wunderkinds. I finally found "normal" fuses from a guitar amp site. Has anyone tried the uber fuses and found the sound better? Hard to understand how it could be. Thanks for any thoughts.
joe_in_seattle

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.
I was curious about the theory that vibration applied to wires and/or electronics would generate some kind of signal. So...I put a high gain phono preamp into a closed box with a speaker system, and blasted it with very high volume sound... much higher than it would experience with a normal setup. What came out of the preamp was absolutely nothing. No measurable voltage and no audible signal.

Vibration is certainly bad news for turntables, for tube electronincs, and, at very high levels, for disc players and maybe tape decks. But otherwise I don't believe there is an effect.
I was curious about the theory that vibration applied to wires and/or electronics would generate some kind of signal.

Try this. Get a male XLR connector, and solder a 50-100 ohm resistor between pins 2 and 3, and connect pin 1 to the XLR shell - this emulates the source impedance of a microphone. Connect this through a typical cheap guitar-store microphone cable to any reasonably low-noise, high-gain mic preamp, and crank it up to full gain and listen.

Now slap the microphone cable around, and you will hear the effects of cable microphonics - they're obvious. Substitute a typical pro-grade cable (i.e. Belden 8412), and you will hear a significant difference. You might actually be able to repeat this with your phono-cable leads - it's just that the cartridge itself is microphonic as well, so it's less definitive.

But that's of course NOT the reason that some fuses have sand in them. The sand keeps the fuse filament from failing for mechanical reasons (i.e. shock, mounting position) when the fuse is operated continuously near its rated current, and the filament softens.

Pubul57,

The ones I have are Bussmann's ABC. Below are the specs for the 4Amp fuse I use for the mid-range driver that I got from Master-Carr. It doesn't mention whether it is sand-filled or not. I also have the 2.5Amp fuse for the tweeter, and that one is also sand-filled.

Part Number: 71385K29

UL Specification :: Listed
Bussmann Type :: ABC
Littelfuse Type :: 314
Ferraz Shawmut Type :: GAB
Available Amps :: 4
AC Voltage Rating (VAC) :: 250
Fuse Type :: Fast-Acting Fuse
Ceramic-Tube Fuse Type :: Fast Acting
Fast-Acting Fuse Type :: Ceramic-Tube Fuse
Visual Indicator :: Without Visual Indicator
AC Interrupt-Current Rating :: 10,000 @ 125 VAC
DC Interrupt-Current Rating :: 10,000 @ 125 VDC
Diameter :: 1/4"
Overall Length :: 1-1/4"
Specifications Met :: Underwriters Laboratories (UL)
Kirkus...OK. I will try your kind of experiment. The easiest way to do it would be to simply "slap the mic cable around" which goes from an actual mic to my Behringer DEQ2496 spectrum analyser. The analyser is very sensitive and will show sound levels below what is audible when I play my system. I will stuff the mic under a cushon so that the slaps won't be picked up acousticly.

And about the sand, another reason is to prevent violent destruction of the fuse body if it blows. Safety issue.
Be careful, Eldartford -- feedback!! Gain's got to be pretty cranked, and the cushion as you well know is most effective at higher frequencies. Please don't blow something up trying this out . . . the terminating resistor is the best way to be safe to your gear.
Isanchez,

I am sure you heard what you heard and liked what you liked with respect to these various fuses.

1. How long did you leave the fuses in place with current across them for your evaluations? I found that the HiFi Tuning fuses took quite a while to settle down in my amp - much (many days) longer than the amp usually takes to settle down after a cold start.

2. I don't recall if you mentioned anything about directionality in your test. Did you swap directions at all with HiFi Tuning fuses to see if if made a difference?

3. It is entirely possible that the Buse fuses work better to your ears in the Maggies, but may have a completely different sonic signature in a power amplifier. Has anybody tried these fuses in a power amp and compared them to Isoclean and/or HiFi Tuning fuses? In a pre amp or digital equipment?

Knownothing,

1. I let each fuse settle in for about 3-4 days. I agree with you, it takes about 70-100 hrs for the fuses to settle in. This was more apparent with the ceramic fuses for some reason. The glass fuses seemed to settle it much quicker. The Buss fuses needed more time to settle in than the HiFi-Tuning fuses.

2. I did try the directionality of the fuse, but only with the ceramic fuses. I did this after somebody mentioned it in this post. The HiFi-Tunning fuses seem to sound better when the arrow follows the direction of the signal. In my case, this difference was very subtle, so I would say it's inconclusive for now. The Buss fuses seemed to sound better with the UL logo at the end of the signal path, but again I can't tell for sure as the difference was not so noticeable. When going from one fuse to another, the sound difference was very apparent.

3. This makes a lot of sense to me since the circuits they plug in are totally different. As a matter of fact, HiFi-Tuning and Acme Audio fuses seem to work very well with Spectron amps, but I haven't try them in my amps yet. I'm very hesitant to use the HiFi-Tuning fuses in a power amp since they are not UL listed. I don't know the certification situation for the Acme Audio fuses.

I think the results may vary dramatically from system to system. I am extremely satisfied with the results I'm getting with the Buss fuses. In my particular case, the difference is comparable to switching signal cables. The fact that what works for me costs about $1.2 per fuse is the biggest bargain I've come across as an audiophile.
Magfan, yes, try one of your fuses on way and then the other.

Isanchez, my Hi-Fi Tuning fuses have no direction indication or arrow but my IsoCleans do. I have found no consistent pattern of markings on the Hi-Fis to use for deciding which way to insert them.
Curious- i took the top off My MBL preamp and there are 4 fuses in there= would you guys rec. I change all the fuses or just the one by the power source??- thanks,bill

Tbg,

On my HiFi-Tuning fuses, the logo itself has the arrow. I couldn't decide for myself either on which direction to go since I couldn't tell for sure the sonic difference between the two ways.
Bgordon
Some effect can occur with just the main line in, I mean once you get to the other fuses on the board they are stepped down and normally only DC power at that point, no doubt they can have effect on your sound as well, but I suggest depending on what you want to spend try the main power in fuse first and see where it takes you.
Tgb,

I wasn't aware of the directionality issue until I read it here. So I don't know if the direction of the fuse was an intended feature for HiFi-Tuning fuses, or it just happened to be that way.

It seems that the Isoclean were intended to be directional.
Bgordon- Try the AC line fuse first, and if your system/room/ears resolve a difference(that you like), then try the DC rail fuses. Any improvements that one can make in the power supply of their amplifiers should provide a sonic gain. The power supply is what drives your speakers, whether modulated by transistors or tubes, as directed by the music signal. That's the fuction(power supplies) for which Hi-Fi Tuning, Isoclean and Furutech fuses were designed, and hence- where they will work best. Of course they're not just for power amps, but any audio gear with a power supply.
The non fuse magnets that I use all made for a significant difference. The two replaced on the main amp board were kicked up several notches when I replaced the main ac fuse beside the power cord for each amp with the magnets. The difference was large, liken to an upgrade from a stock power cord to one in the 1k range. I have more on order for all of my components now. Tom
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Magnets...Hmmm! Now that's a gem. No wonder manufacturers discourage this sort of stuff.
Yes is the answer to no protection. Yes is the answer to better sound. Yes is to the fact that I removed the ferrous cover to my ac mains. Yes is to the better sound resulting from the removal of said cover. Yes it is still covered, now with a non ferrous material. Yes I hope to replace the entire box with a non ferrous enclosure. Yes I believe my system will sound better as a result. Tom
I've had good results removing ferrous material near my equipment but it depends on the equipment and the situation.

What I'm saying, I don't doubt you got good results.

I hope you don't think I'm picking on you, I honestly do not know what the "non fuse magnets' are, or even how they work. Asking if they provide protection was because the description is "non fuse."

If it works for you and you're happy, it does not matter what anyone else thinks. Most of my equipment needs fuses because I run all tube. If a tube shorts out and there is no fuse, then something gets burned.
Albert, I don't think your picking on me. I am just reporting to those out there my experiments, trials and results. I don't expect others to try what I have. Reading someone else's idea, experience or result may trigger an expansion of that idea or add a new direction and possible benefit. One expansion of discourse posted here is the possibility of controlled resonance of a vacuum tube filament within the confines of the glass. Tom
I've always wondered why the hi-end manufactures do not put these in right off the bat. Makes sense to me. Its one thing to let people buy the cabling they want but finish the job on the inside of the gear. Add the better fuses!
Dvrs -- some manufacturers are doing that -- such as Dan Wright of Modwright who posted some comments here.
Well- my guess would be many don't for the same reason the high-end tube gear manufacturers don't install NOS tubes. Too many consumers can be satisfied with newly manufactured Soviet or chinese tubes, and of course- the price of NOS tubes would be exorbitant. Better(and cheaper) to let the buyer sate his(or her) own tastes. Even these fuses(Hi-Fi Tuning, Isoclean, Furutech) each affect a system's sound in a different manner. Then again- I'm certain there are those that(like many in here) haven't tried them, and don't believe they offer any improvement.
I bought a modified Jolida JD-1000 that had the top level modification offered from Parts Connexion. I was surprised that for the price of the mod they were not included. I can see why NOS Tubes are not used though. Much more of an expense and the fact there is a rarity issue with most of them.

I would bet that if many more companies added them customers wouldn't bawk at having a Furutech over a Hi-Fi Tuning or an Isoclean. I think they would be fine with it.
Installed another non fuse magnet today. My wife came down and said the bass was shaking the house. She was two floors up. One half hour earlier playing the same passage at the same volume setting she didn't complain at all. The non fuse magnet I installed was in my transport. This is the only fuse and is on the ac side. I have three more to go. One each in my two sub-woofers and the last to be in my pre-amp.

Can you have to much or to refined a power supply? Is not the power supply the point source from where all gain stages arise? So why not upgrade the point of entry into the first stage of any device. Upgrading the fuse integrity is an extension of a power cord upgrade. Tom
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Grant I respect you as well,

As I responded to someone else on this thread. I don't expect everyone to do as I have. Just here to relate my experience. You know Grant it all starts at the power supply so any component upgrade there is a pass thru all the way up the food chain. Select whatever fuse device sounds the best and makes you feel safe. Tom
Theaudiotweak,

Do you turn everything off (or unplug it) when you leave the house?

Do you have a fire extinguisher handy when you listen to music?

This may sound funny, but I am serious.
Sir Knownothing,
Thank you for your concerns. I too am concerned and careful with the use of the magnets in my hi-fi. I have had one product over 30 years flame out on me and the internal fuse did not blow or trip the dedicated circuit breaker located next to the equipment. I have a dedicated method of turning all equipment on in a set sequence and then turn off in the reverse sequence. I have always done it this way, pre magnets or post.

Much of my listening is done in the early evening with this system watching satellite tv on a front projector and retractable screen. After a couple hours the system is juiced up and stable enough to switch over to some serious listening. Thanks for reminding me of the fire extinguisher right over there by the fireplace. I have in the last several months been shutting the system down, before the installation of magnets, trying to save the planet. I will in the next couple of days install the last magnet in my Belles 21a preamp even with its use of two 12au7's. This preamp is very simple in its number of parts and super stable in all performance aspects. It does have a remote with volume, mute and power. I have answered my own concerns and maybe yours as well..Thanks for asking. Oh, the ac mains box now with no door, though covered is on an adjacent wall 11 feet from my chair. Tom
Theaudiotweak,

Well, I own stocks. What kind of fuse does somebody use for that?
Magnetic "fuses". Where do these idea come from? I suppose the next step will be radioactive fuses. Even more mysterious, and therefore commanding even higher prices.
I am going to replace my line fuse in the Krell SACD standard and my two subwoofer fuses as well...will report after burn in!!
I suppose the next step will be radioactive fuses.
as your amp disappears in a small mushroom cloud!
.
Dr.Know

The size of the fuse depends on your risk tolerance. I have had erratic sleep patterns over this stuff. Friday though was a great day especially if you had doubled down the day before. Saturday I will install the last magnet in my tube preamp..six will be the final number. Tom
I suppose the next step will be radioactive fuses.

Excellent idea. Buy an old broken radio and install the radioactive fuse.

BINGO, the radio becomes active again and picks up everything.
I can't use Magnetic Fuses 'cause of the Steel Plate in my head. I hear a whistling sound.
Theaudiotweak..."Tube" preamp you say. Perhaps you should be concerned about the effect of a magnet on the electron beams in your tubes.

At work, when testing a vidicon to calibrate it we found that the results varied depending on which way the device was pointed. (A vidicon is a vacuum tube imaging device, once used for TV). Turns out that the earth's magnetic field was deflecting the electron beam. Of course we all know what a speaker magnet does to a CRT. However, the good news is that, unlike transistors, tubes are not damaged by radiation.
Eldartford,

I am concerned about that issue of bending the beams. I think the sound advantage that I gained with the use of the magnet may be further enhanced with the addition of a Faraday shield. Any disruption depends on where the magnet is relative to the tubes or other critical circuits. In each case so far whether on the ac or dc side of things there has been an increase in audible performance. From the visual side I really think the display of my transport became slightly brighter and easier to read off axis with the use of a magnet instead of line fuse. The fuse holder is internal otherwise I would do a quick swap out for comparison,to be sure.

Some one here said that a fuse element vibrates. Well of course everything vibrates or resonates. So maybe these fine resonances within the fuse line itself is an influence on purity of the ac or dc line voltages even after the filter stage. If this is true then to me it seems like the filament of a vacuum tube would also be at risk for these same self generated resonaces. Same tube type different material structure of the filament would generate a different resonant structure while conducting. Tom
Theaudiotweak, vibrations are why I think tubes whether from within or without are improved with resonance control devices, such as the Acoustic Revive QR-8 and especially AVM painting.

What is of interest to me with using magnets to replace fuses is what does the magnetic field do? Does it shape the ac fields but also does it influence those components that are nearby? This entire idea seems to come from out of the blue, but maybe it is my deficiencies in understanding electro-magnetic interactions.