Enjoy it Vince.
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Well done lonson !!!
Best wishes
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You take the cake, Vince. Enjoy.
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I did try an SR Blue (half price thankfully). I still have it. To my ears, made no difference to my Innuos streamer.
Comparing to active parts of car systems is irrelevant.
I started by actually taking the trouble to look up the specification of the wire in certain fuses. They tend to be lead/tin/antimony alloys. They have very low resistance and it does not change significantly up to the rated current, nor do they start to warm up. The metal is chosen because of its high heat coefficient and low melting point (250-300 celsius), although this is many times above normal operating conditions.
If you look at Littelfuse, a big US manufacturer sold in the UK, designed for audio and medical applications, a 2A fuse at 250v has a resistance of 0.0546 ohms. With a 2A load the voltage drop (from increased resistance) is 190mV, that’s 0.19V, a reduction of 0.076%.
So the idea that these fuses restrict current flow is just nonsense. The device will draw as much current as it needs, the fuse will offer nominal resistance and a stable voltage. Only in extreme fault conditions will the values change and it will blow.
The data sheet is here:
The full guide is here:
These are high quality fuses made for scientific and audio use and cost about $3 each.
I asked the QSA importer about the Graphene and he replied - and these are his exact words:
“The Graphene mix indicated is not an internal change it is the application of Graphene strips ( but not in all cases or levels of the products) to the exterior casing as can be seen in the image you have sent ( image on the left).”
So the graphene is apparently these little black strips on the outside of the fuse. Go figure.
You can believe all the fuse marketing, but most of it is just outright lies (as was admitted by the guy with the Sluggo things) or epic amounts of irrelevant BS.
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FWIW, based on my (somewhat limited) understanding of the principles involved, I expect the Fuse Box/Sluggo combination to outperform most, if not all, fuses.
Looking forward to @aangen ’s listening impressions…
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When and where was this “admitted”, and by whom? And, please be specific, if you care to elaborate.
Just interested in trying to keep the various opinions and claimed facts about aftermarket fuses as clear/straight as possible…
TIA
I quoted what the Swiss Fuse Box guy said on his website here:
After a period of consultation, he replied, says I was correct ("… makes a fair and intelligent argument, and is correct… ").
He then came out with a lot of complete nonsense about macro and micro (who on earth would design an amplifier that made transient demands massively above the fuse rating?) and that they didn’t really know.
The second stage of guesswork/whataboutery was vibration. I quote: “There could also be the possibility that fuse element vibration is at play as well, but resistance is the only measurable phenomenon we can point to.”
The irony is that the $5 Littlefuse cartridge fuses are tested for vibration to a US Military standard called MIL- STD-202, Method 201. It’s on the spec sheet I posted earlier, it involves measurements before, during and after the vibration is applied (for hours). You can read the details here.
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… and of course the marketing BS is still there, unchanged, even though it is accepted to be untrue.
I sent him the littelfuse data sheet at the time to make the point that fuses don’t heat up and increase resistance / drop voltage during normal use.
https://www.underwoodhifi.com/products/fuse-box-swiss-digital
That is not true. The electrical current that is passing through this fuse, just like a power cable, or a power regenerator eventually ends up powering your speakers that makes the sound. If it picks up any dirt or contaminants like EMI’s and distortions from vibrations, it will pass it down to the speakers. Depending on how revealing your system is, you will hear these differences in the power from your speakers.
A after market fuse is not just a thin wire that melts when the current is too high, it contain other parts that can absorb vibration and EMI as well as pass current to your system. Those parts can help quiet down noise and distortion in your power.
Here’s a picture of a Beeswax fuse I broke open to see what’s inside. Besides beeswax it has other ingredients that can reduce electrical noise and restrict current flow.
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I don’t see a connection between what you wrote and what I inquired about.
As usual, I don’t seem to be able follow and agree with most of your premises, support and conclusions, in the context of when/how they are proffered.
Mr. Shifter’s response to you, as quoted, does not seem to be related to your sweeping condemnation of after-market fuse manufacturers as “liars” in relation to their claims about the audible impact/performance of their wares.
But, maybe I am just missing tour point?
Rather, the back and forth appears to be about how fuses behave (in terms of heating, expanding, etc.) when current is applied.
Please know I am more or less agnostic on the aftermarket fuse question, and I am not defending any charlatans or related behavior.
As I previously posted, I did note an audible improvement in the sound of my Disc/sStreaming - centric system when I removed a SR fuse from my P10 regenerator and replaced it with a “Swiss Digital Fuse Box”/copper “Sluggo” combination.
This experience has sparked my curiosity about the claims of aftermarket fuse manufacturers and purveyors.
I understand ceramic fuses generally include silica or similar. It dissipates heat and is a safety feature should the fuse blow. It’s part of the specification.
Can you please explain what you mean by “restrict current flow”? Surely during operation a device will draw the current it needs. The fuse is only there if there is some fault and the current draw becomes far too high. The fuse shuts off power to protect the device, stop it catching fire etc.
As the fuse has such low resistance in normal use, the current flow will never be restricted?
“restrict current flow” just seems to me to be repetition of the marketing (this terms is used repeatedly) rather than any consideration of that actual properties of fuses under normal conditions.
The littelfuse fuses are made to military specifications, very tight tolerances for medical and audio use, and have gold/rhodium plated caps to avoid corrosion. One of the main features of fuses is how their rating changes with ambient temperature, which is very relevant to portable or mobile medical or military equipment. The litttelfuse perform better than Bussmann, but the latter is a domestic product. This is probably of more relevance given how hot some audio stuff gets.
My point to Mr Shifter that he was selling the Swiss box on incorrect science (how fuses behave). He accepted I was correct, coming up with some questionable alternative theories.
His product replaces the wire fuse with an electronic fuse (this is not a new concept) and if your amplifier blows up using it it’s your problem, not his (read the small print). This is a risk some people take without a Swiss box.
The only fuse I can change in my system I tried a SR fuse. It made no difference and I’m not surprised - after the fuse the power goes through a voltage regulator, transformer and linear power supply before it gets to the electronics.
I have not changed any of the other fuses. They are all 13A safety fuses. SR, QSA and Russ Andrews all rebrand Bussmann 13A fuses, so why pay £8,000 for a £0.30 fuse? I have a 13A AMR fuse, but I contracted AMR and they told me not to use it as they’ve lost the certification!!
This looks to be excellent reading for anyone considering fuses for audio gear, after a quick scan through.
that’s my small-hours reading sorted tonight 
That’s really quite simple. Different materials like copper or silver or anything else has different resistance to electrical current and that can influence the timing of frequencies going through the conductor. I have noticed silver does not sound like copper or aluminum. Are you related to AMR?
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Well put Clifton…
All he can do is present links to fuse little fuse et all which of themselves
say nothing about making fuses for HiFi Tuning (which makes melt wire
from materials sourced from Mundorf) or Audio Magic handmaking there own
own products…Or Ted Denny sourcing fuses from someone else only to modify
them…
Another thing is that Little Fuse does make audio related and medical grade
level fuses…so here we go go again…if fuses don’t make difference to sq
then why would Little Fuse make medical grade and audiophile fuses?
So an ASR acolyte…you hit it on the head Clifton…
Best wishes
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Assume the transformer has 18awg wire, resistance 20 ohm/km = 0.0004 ohm per 20mm (length of fuse). 2A fuse resistance is 0.546ohm = about 130 times as much, so same resistance as about 3m of 18awg copper. If you think how much copper there is an amplifier’s transformer - 50m?
So the fuse might be adding a few % at most to the resistance of the circuit from the incoming mains to the transformer, and that’s measured under a full load. Will be lower as most components operate at a small fraction of the fuse rating.
How can it “influence the timing of frequencies” when it is not on the signal path?
Why should I be related to AMR? I was given some AMR 13A fuses, I gave two away, I have one here unused and it won’t be used.
There you go with this measurment thing again. I wish sound quality could be measured, then we wouldn’t be having this conversation.
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Here is my problem/disconnect with regard to your point and reply to my questions –
As far as I know, the following IS (more or less) true as a description of how fuses “fail”:
“…the current flowing through it causes the fuse filament to get warm because it is, in fact, a small value resistor. It uses Ohms Law…As the current through it increases, the heating of the element increases, until the conducted current exceeds its current rating, when, ultimately, it burns through and opens the circuit …"
So, for whatever reason, I just don’t “get” your point, nor its relevance.
That’s O.K. I just would prefer more clarity when you (or me or anyone else) posts conclusive, unequivocal declarations of fact or “truth”.
Appreciate the civility and consideration displayed throughout our various back and forths…
Cheers.
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That quote is just about entirely untrue, and Mr Shifter accepted that.
Up to their current rating, fuses do not warm up and their resistance does not increase beyond a trivial amount (0.19mV for a 250v 2A fuse).
Nor do they blow at their current rating. A typical cartridge fuse will exceed its current rating by 35% for about 30 minutes.
Ohm’s Law is an empirical generalisation, and does apply to fuses at their critical point. Ohms Law implies a linear relationship between current and resistance at a fixed voltage. In fact fuses have an S-shaped relationship.
So I can’t see one truth. I’ve given you the data, everything you need to know about fuses, all you have to do is read it, like @joma0711 . Or you you can just continue believing the fuse-BS. I just don’t know a simpler way of saying it.
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