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Direction of aftermarket fuses (only for believers!)

It is with reluctance that I start another thread on this topic with the ONLY GOAL for believers to share their experience about aftermarket fuses.
To others: you can call us snobs, emperors w/o clothes,... etc but I hope you refrain posting just your opinion here. If you did not hear any difference, great, maybe there isn’t.

The main driver for this new post is that I am starting a project to mod my NAD M25 7 ch amp for my home theater. It has 19 fuses (2 per channel, 4 on the power supply board, 1 main AC) and I will try a mix of AMR Gold, SR Black and Audio Magic Platinum (anyway that is the plan, I may try out some other brands/models). As it is reasonably difficult to change them, esp the ones on each channel module that requires complete disassembly, I would like to know what the direction is for these models mentioned and of course, others who HAVE HEARD there is a difference please share your experience on any fuse model you have tried.

Fuses are IME directional:
Isoclean is one of the first to indicate the direction (2008/2009) on their fuses. Users of HiFi Tuning (when the awareness rose quite a bit amongst audiophiles) have mostly heard the difference.

As an IEEE engineer, I was highly skeptical of cabling decades ago (I like the speaker design of John Dunlavy but he said on many occasions that cables nor footers matter at all, WRONG!). Luckily, my curiosity proved me wrong as well. I see the same skepticism that I and many others had about the need for aftermarket cables many, many years ago now on fuses and esp on the direction on fuses.

Another example is the direction of capacitors (I do not mean electrolytic types). Even some manufacturers now and certainly many in the past did not believe it can make a difference sonically. Maybe some do but it takes time in the assembly to sort and put them in the right direction/order (esp as some of the cap manufacturers still do not indicate "polarity") so that maybe is one argument why this is not universally implemented.








jazzonthehudson
jea48
4,788 posts
 

I would add IF the contact between the fuse end caps and fuse holder clip/s contact/s are such that a VD can be measured (From fuse clip to fuse clip) then what else can/is going on in the poor connection? Maybe an ever so slight arcing between the fuse end cap/s and the fuse holder clip/s? If the fuse holder in mounted directly to the circuit board in close proximity of electronic components who can say if the ever so slight arcing can be sending/spewing out RFI infecting the electronics? Who can say if the arcing is causing a vibration on the circuit board? Is there is energy being created by the ever so light arcing? What impact might the energy create by the arcing have on the electronics of the piece of equipment.

Like atmashere said in an earlier post his preamp’s power suppliers are regulated so a small AC Line mains VD would not have any impact on the SQ of the preamp. But what if the connection between the fuse end caps and fuse clip/s was such that a VD existed, therefore maybe, an ever so small arcing was happening. So, what IF?

Jmho, the differences heard in SQ is not from minuscule resistance of the fuse element inside the fuse that measures higher in one direction than the other, which is said to create a minuscule VD across the fuse element, measured in a live completed circuit from fuse end cap to end cap.

atmasphere's avatar
atmasphere
12,171 posts
 
^^ You won't have arcing- that would be audible! A small amount of arcing has a way of turning into a lot of it in a short period of time...

Its easy to measure the voltage drop on almost any fuse in series with the AC line. There has to be one- as the voltage drop represents heat, and when the heat gets high enough that blows the fuse. IOW, the fuse is a resistance in series with the load.


geoffkait's avatar
geoffkait
23,365 posts
 
Jea48 wrote,

"Jmho, the differences heard in SQ is not from minuscule resistance of the fuse element inside the fuse that measures higher in one direction than the other, which is said to create a minuscule VD across the fuse element, measured in a live completed circuit from fuse end cap to end cap."

No one ever said or suggested differences in sound quality are due to the minuscule differences of resistance of the fuse element inside the fuse. That’s a Strawman argument. Even the independent tester for HiFi Tuning states on the data sheets that the very small differences in resistance DON’T EXPLAIN the (obvious) differences in SQ. All the resistance measurements are intended to show is that that ARE measurable differences, thus an indication that SOMETHING is going on. As I stated earlier on this thread somewhere and as HiFi Tuning intimates on the data sheets, distortion and noise measurements might be more uh revealing in terms of sound quality.

Geoff Kait
Machina Dynamica
no goats no glory
Post removed 
jea48
4,788 posts
 

I’m reminded of a post by herman.

Quote:

"If you say the AC fuse blew because there was too much current flowing through it everybody nods in agreement even though that isn’t true. If you say the wire in the fuse melted because it got too hot after absorbing energy from the electromagnetic wave people look at you like you are insane and want to argue that vibrating electrons constitute current flow."




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