Fuses fuses fuses
Not to make too fine a point of it, but has anyone here noticed that I have confirmed by measurement that if you place the fuse in backwards that you may indeed hear a difference? Those that say otherwise raise their hands: Take another look at my posts on this topic. In all of them you will see that I confirm that what is being claimed as heard could be real and that it can backed up by measurement. The thing that seems to be tripping y’all up is that the measurement confirms what you hear and at the same time shows that the phenomena is **not** due to a fuse being directional but instead just simply the resistance across the fuse is different. BTW, from the HiFi Tuning website, we find a PDF document with fun facts about these fuses: http://www.partsconnexion.com/prod_pdf/hft_facts.pdf Note that they list different resistances depending on direction. But also note that the resistance is stated in ’mOhms’. Its unclear what the small ’m’ is for, but if that is ’milli’Ohms then their measurements are a mile off. On the HiFi Tuning fuses we have here, they measure about the same as the leads of the meter do shorted together, about 0.1 ohm. In milli-ohms that would be 100 milli-ohms (but we know that the probes are that much already, so the fuse is much less), so my guess is that by the ’m’ they are probably trying to say ’micro’ (which is normally expressed with a ’u’ which is as close as a keyboard can get to the Greek symbol Mu). I’m not sure how you would measure that accurately, but one thing is certain and that is the meter and probes used for the test plus minor resistances across the contact of the device itself are likely responsible for any differences seen. Heck, if you simply took the same measurement twice with a meter with that resolution (which is a very expensive meter) you would likely find larger differences without reversing the direction! So I think we can see that the idea of the manufacturer’s PDF as suggesting directionality is completely false. A better interpretation is that the *average* resistance of the fuse is going to be in that ballpark. I think they have done a mis-service as these numbers, when so obviously misinterpreted, spark a lot of useless debate. Now I’ve already shown why there is directionality and that its not something within the fuse. This is confirmed by the numbers I’m seeing on the HiFi Tuning PDF- the latter are far too small to play an influence in the voltage drops I’ve measured! So again: reversing the fuse can be audible, even though the fuse itself is not directional. So the people that hear this and find it repeatable are probably hearing it (unless they are experiencing expectation bias) and those that don’t may not be hearing it (unless they are experiencing expectation bias). |
Yeah I read it Ralph and am mystified why Geoff didn’t acknowledge it in his explanation which completely avoided it. It is a truism in audio that MANY things can affect sound, often in quite subtle ways, some more profound, of that i’m a witness . Unfortunately it is often taken as a monetary opportunity for some that make their livelihood by exploiting for profit, sometimes substantial, the differences. Geoff wouldn’t you agree that Audioquest has a vested interested in promoting "truthful hyperbole"? It’s all about marketing savvy and understanding the customer. Hundred dollar fuses, really?😂 Reminds me of a very wise man I knew many years back and a saying he had that never left me,, "you’very got a buck, how do I get it". So WHAT is the "magic" in a hundred buck fuse that makes it cost what it does Geoff, must be marketing costs, right? Or is it literally just worth more than it's weight in gold, or at least close to it. |
Thanks, Ralph (Atmasphere). I’ve been assuming that the "m" in the HFT paper stands for "milli." If in fact it stands for "micro" then the 0.000038 ohm figure that has been cited to illustrate how miniscule the differences are in their measurements for the two directions would actually be 0.000000038 ohms! Although I’m thinking that "milli" may actually be the correct interpretation. For example this Littelfuse datasheet lists for their 3AG Series 313 glass-bodied 6.3 x 32 mm slow blow 2 amp 250 volt fuse a "cold" resistance of 116.9 milliohms. Which is very close to the numbers shown in the HFT paper for a T 2 amp 6.3 x 32 mm "standard glass fuse" if "m" is interpreted as milli and the commas in their numbers are interpreted as decimal points. Fuses having significantly higher current ratings have much lower resistances, of course, with the resistance of the 10 amp Littelfuse in that datasheet indicated as 8.3 milliohms, which seems consistent with HFT’s measurements of their own fuses having relatively high current ratings. (Their paper doesn’t provide measurements of standard glass fuses rated above 3.15 amps). Either way, though, I of course agree with everything else in your post, and it is consistent with and further emphasizes what I, some other members, and others who like yourself are designers of highly respected audio electronics have said here in various fuse-related threads. Best regards, -- Al |
tubegroover Yeah I read it Ralph and am mystified why Geoff didn’t acknowledge it in his explanation which completely avoided it. It is a truism in audio that MANY things can affect sound, often in quite subtle ways, some more profound, of that i’m a witness . Unfortunately it is often taken as a monetary opportunity for some that make their livelihood by exploiting for profit, sometimes substantial, the differences. Geoff wouldn’t you agree that Audioquest has a vested interested in promoting "truthful hyperbole"? It’s all about marketing savvy and understanding the customer. Hundred dollar fuses, really?😂 That’s got to be the dumbest thing anyone said so far. What possible financial motive would Audioquest have in promoting cable and wire directionality? Heck, most audiophiles are like you and don’t believe it anyway, and wouldn’t buy it because you think it’s a scam. But to further destroy your silly argument Audioquest is by no means the only cable manufacturer selling directional cables. In fact any cable manufacturer that wants to compete for audiophile dollars must certainly be aware of directionality and actually mark their cables accordingly. Anti Cables obviously, Goertz, and I’m sure many others. Not only that almost all high end cable manufacturers cryogenically treat their cables. Why? To be able to compete. So what have we learned here. It’s performance that drives the market of cables not hyperbole. Duh! |
