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.








128x128jazzonthehudson

Showing 2 responses by gs5556

How does one know if the markings are placed in the proper orientation by the seller? If the seller manufactures the fuses and determines the correct orientation or if he buys them OEM and places them a certain way during the treatment process, then all you have to do is ask him. Otherwise, whatever comments are offered are meaningless since the fuses are randomly oriented when marked.
Took a look at hi-fi tuning measurements and they are meaningless. The data presented indicates the measuring instrument has a resolution of 0.001 milli ohm. The readings shows an average of 40 micro ohm difference in each direction.

That is the proof of directionality? Hardly. If the ambient air temperature should rise by 0.1 degree C as you change the probes around, that would be enough to close the difference to 10 micro ohms. Not to mention that the surfaces of the fuse contacts must be accurately milled for those readings to occur everywhere around the fuse. Not to mention the fuse elements have to be cut to the precise length and diameter each time.

If you hear a difference in one direction over another, you get no argument from me. But don't show me numbers and say this proves it.