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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.








128x128jazzonthehudson
geoffkait's avatar
geoffkait
23,365 posts
 
nonoise
2,177 posts
05-13-2016 2:34pm
"Thanks Geoff but that does sound daunting.

If anyone cares to look at my above post there’s a link at the beginning of the first sentence that’s partially obscured by the blue background. In it, is a short review on about 11 fuses and how they sound to the reviewer."

I would prefer if possible to get the full Monty report with at least 100 hrs of break in for each fuse. 18 hours on a break in device seems way not long enough. I maintain that you can’t tell if the deficiencies Eric reports are real or if they’re simply the result of insufficient break in. I would prefer the BREAK IN track on the XLO Test CD played on REPEAT for say two weeks. I also would have preferred to see at least the SR Red Fuse in the mix not to mention the Black Fuse. Also the Audio Magic Beeswax fuse or at least the AM Super Nano fuse. And the Isoclean fuse. If you want a super cost effective fuse just try flipping a LITTELFUSE fuse or ANY stock fuse and see if that works.

Addendum: at least Eric tried and for that he is to be commended. I also happen to agree with Eric that the diode symbol on the HiFi Tuning fuses is not intended to show the correct direction the fuse is to be inserted, only to provide cosmetic asymmetry to the fuse so you don’t lose track of it’s direction when flipping it.

Cheers

nonoise's avatar
nonoise
10,590 posts
 
Thanks Geoff. Your mention of the XLO Breakin Test CD reminded me that I need to get one of those for regular maintenance. Audio Advisor and Music Direct both have the Ayre Test CD so I think I'll give them a look.

All the best,
Nonoise
jazzonthehudson's avatar
jazzonthehudson OP
277 posts
 
Nonoise, thanks for the links. I just contacted PADIS in Germany and will report back.

Al, as always, I appreciate your input and great to point out to put things in proper perspective, which I always try to do at the end. The rationale for pimping my M25 is to get my home theater system closer to my main system (both have Dunlavy/Duntech speakers). Next year, when junior is out of the house, we will relocate as our property tax is very high, thereby very likely downsizing from 3 to 2 audio systems. I tried my HT system with expensive HFC cabling and it sounded terrific, but not for my wallet’s liking to keep HFC both in the main and HT system. So for the M25 I will just upgrade the 3 main channel fuses and the main fuse, the rest will get the AMR/Little Fuse upgrade. The processor gets 2 new fuses as well.

As for the best value/money, my home office setup beats all but then again, sometimes one needs a bit higher SQ.
davidpritchard's avatar
davidpritchard
866 posts
 

When downsizing I found a second system based on a premium headphone (such as the Sennheiser 800) and a dedicated headphone amp to be a source of great pleasure.

The degree of progress in headphone systems over the past 7 years has been staggering and worth exploring.

David Pritchard

mapman's avatar
mapman
21,888 posts
 
If downsizing don't underestimate the potential of newer Bluetooth speakers and systems as well. 
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