As an IEEE engineer Google failed to answer me on this- what's an IEEE engineer? |
This was the first thing that came up when I googled it: I saw that too. That's an organization, not a field of endeavor like mechanical or electrical engineering I'm also an AIAA engineer. Given your posts here, highly unlikely. |
in fact I was involved at one time with third party testing for VERY big projects, you know Government and Military projects. $2000 hammers? |
Al, if you (and Atmasphere) really were thorough you would simply eliminate the fuse holder entirely, no? No. That would never meet UL, CE or other directives. |
If y'all are interested, I think I've sorted out what this reversal phenomena is all about.
It has to do with the fact that the connections on fuse holders are not perfect. The act of reversing the fuse sometimes gets you a better connection. However, directionality really isn't the issue. Similar to a power switch, the contact area of the fuse holder that is actually doing the work is a fraction of the total contact area. As a result, if you simply rotate the fuse in its holder, you will find that there is a best position where more of the fuse holder contact area is touching the fuse contacts. When the fuse was reversed, on occasion you got better contact or worse contact, which appears initially to be a directional issue, but that is really an illusion.
Interestingly, this effect is measurable as a voltage drop across the fuse holder. As you might expect, the less voltage drop the better. So it is possible to adjust (rotate) the fuse in the holder for minimum voltage drop and thus the best performance. A side benefit is the fuse will last a little longer as the operating temperature is reduced.
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I meant if you wanted to get to the truth you would eliminate the fuse
holder from the equation. You know, for the experiment. Capish? Whether
or not aftermarket fuses meet UL, etc. is irrelevant to the question of
directionality. You don’t really think audiophiles care if their fuses
are UL listed, do you?
UL is a directive? You make it sound like a requirement. I'm chalking this one to not having read my last post. |
I read your last post. I read your last two posts. Did I err? Did I misinterpret something? As far as I can tell, you misinterpret on purpose. That makes it hard to have a conversation. Example: Or maybe you’re insinuating that any person who doesn’t get the results
you’re looking for isn’t honest and careful, it’s hard to tell. Al does not insinuate. You are one of the very few I have ever seen to attack Al, who IMO and that of many others is an important asset to this site. You might consider ratcheting down the rhetoric. |
just to set the record straight, UL is not a requirement or a directive, it’s a guideline or standard. I did not state that it was. I did state that the CE mark was a directive, and that there are others. You simply chose to misinterpret, as part of your on-going program to make others wrong. The insinuation that tests that don’t get the "right" results are not
honest or careful is rhetoric. His rhetoric. I’ve already pointed out
that a scientifically correct test would eliminate the fuse holder
altogether. Al is not prone to rhetoric. OTOH such seems to be your lifestyle. A scientific test would not eliminate the fuseholder, not if you actually wanted to know what is going on. |
What exactly are you insinuating? That your technique is to continuously troll until you’ve beaten people down. Its not a way to further discussion, merely a method of making yourself always right all the time. You can test the fuse holder separately if you really were interested in arriving at the truth. I realize you and Al are just playing Ivory Tower, and have no interest or plan to test either the fuse or the fuse holder. That’s the difference between a Skeptic and a Sceptic.
This statement is false and is an example of the trolling behavior and rhetoric to which I referred. I did point out on a different thread that we found issues with fuses a long time ago, and in 1990, designed our MA-2 with an entirely different kind of fuse and fuse holder on the basis of improved performance. Apparently Geoff has forgotten the fact that I joined this thread recently with some results on testing. Those results are that the directionality appears out of coincidence and that actually greater improvement can be had by rotating the fuse in the holder for best contact. The improvement is measurable and audible; descriptions others have made on this thread of what happens when you get the direction right accurately describe what happens when the contact area is maximized. Occam’s Razor has something to say here! Given that a fuse has to be used in AC circuits and given that people report differences by reversing the fuse, and also understanding how fuses are inherently incapable of having directionality in any way whatsoever, the explanation that they somehow have an effect by reversing them in the holder is a fairly complex explanation: some sort of unknowable, unmeasurable quality of the fuse itself. A simpler explanation is that the reversal is improving the contact area because fuse and holder are not dimensionally perfect and the fuse might sit better in the holder in one direction. By rotating the fuse in the holder without reversing it gets the same effect only more profoundly. |
And thanks also for the compliments you extended in my direction in some of your other recent posts. They were long overdue. |
Therefore, going by Occum's razor as Atmasphere suggests, the hypothesis
with the fewest assumptions would be that the fuse itself is
directional, not the fuse holder. This is a classic strawman, and like all logical fallacies, is false by definition. I was not at any time suggesting that the holder was directional. Millivolts...... If that was the
reason, wouldn't the same reasoning hold true for the AC mains line voltage
feeding the fuse? In other words a small VD in millivolts on the mains feeding
a piece of equipment could/would have an impact on the SQ of the piece of equipment. Not hardly....
Its more than just millivolts- I can measure the effects with a 3 1/2 digit voltmeter. Mitch2's suggestion by the way is excellent and is also measurable. Some fuseholders (like panel mount units) won't allow this. |
Millivolts...... If that was the reason, wouldn’t the same reasoning
hold true for the AC mains line voltage feeding the fuse? In other words
a small VD in millivolts on the mains feeding a piece of equipment
could/would have an impact on the SQ of the piece of equipment. Not
hardly.... You are correct in your first statement of this paragraph. An important question might be 'what is meant by 'small'?' In one of our preamps I measured a 158mV (0.158V) drop; in one of our amps I've seen a 2 volt drop cause a loss of 40 watts at the output of the amp. In the case of the preamp the power supplies are heavily regulated so I do not expect to hear anything from a voltage drop on the line nor do we in practice. So we can assume that some types of equipment are far more sensitive to this issue than others! The line voltage determinately effects the sound of a lot of equipment. This should come as no surprise to many of us here who have experienced the system sounding like Nirvana on one evening and the next day falling well short. So much has to do with line voltage which fluctuates, but also with how easily the line voltage can sag as the equipment is running (a further issue is distortion of the AC sine wave which is not part of this discussion). A fuse is one of those spots in that set of connections from the wall (AC power connectors, power cord and the fuse and holder) that is likely the 'softest' which is to say that the sag occurs easier at that point, due to contact area and conductor size (the effects being limited by the fuse being so small). Part of this is due to the nature of the fuse itself, the other part due to its connection into the system. This ties directly into the power cord conversation (a very real and measurable phenomena) and its effect on the system sound. On a different website I encountered an individual who was of the objectivity camp (measurements) who was adamant that power cords could not make a difference in system performance. When challenged on the subject, I discovered he had never even tried to measure the performance of a power cord and thus had no measurements! To individuals who live and die by measurement, I appear to be a subjectivist; I found it quite ironic that he lacked the measurements while I did not. I'm not sure how I come off on this site but to be clear I like to know why I hear certain phenomena and so try to see if its measurable. Quite often it is. In this case, its a simple fact that you can measure the voltage drop across the fuse. Depending on the equipment in use and your measurement technique, you can see that voltage drop vary somewhat with the audio signal. It could be construed that this could introduce IM distortion. IM happens to be audible to the human ear so it should come as no surprise that the effects of the fuse can be heard. Our customers have been saying this all along as I have maintained elsewhere on this site. It took the obviously specious argument that the fuses were somehow directional to cause me to take a look at why people might think that. A simple DVM showed why and anyone who puts the DVM in AC voltage mode and simply measures across the fuse connections will see a number appear on the meter readout. This is not hard to do! Further measurement might show that by rotating the fuse in the holder the voltage drop can be altered. Sometimes you might have to reverse the fuse to optimize the contacts because the fuses we are dealing with are not always perfectly dimensioned so it might get better contact area in one direction as opposed to another. This does not mean that they are directional- it simply means they are not built precisely. |
I hate to judge before all the facts are in but it appears your entire
argument hinges on that statement, yet it is strictly hypothetical and
specious.
Not at all. I used the word 'might' as with some fuseholders and fuses, the voltage drop stays about the same due to the alignment of the contacts. This easily explains why there are inconsistencies in reports. I also happen to be rather skeptical that anomalies in pressure or
contact surface can actually explain the differences in soundstage,
dynamics and tonality among other things that have been reported by many Given your constant trolling, this such should come as no surprise. In your case I suspect its more profitable if the explanation remains mysterious and tricky to explain while using words like 'quantum'. |
^^ 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.
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^^ Arcing is often audible with audio equipment. An arcing power switch can make quite a racket!
If you have arcing in an older house wiring system, failure of the arcing component (wall socket or the like) is eminent. It can also be a fire hazard.
Any connection has a certain amount of resistance. As current flows through it the resistance causes heat. A cold solderjoint will heat up faster than a proper solderjoint.
When a fuse blows, it will be warm or hot if you remove it at the time of failure. Its heat that blows a fuse. So it should be no surprise that any fuse runs at a temperature and that there will be a voltage drop across it. Keeping the voltage drop to a minimum by optimizing the contacts helps the fuse as it will run cooler since the heat it makes is supposed to be made by its internal element not its contacts.
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^^ Do you understand how power cords are wired? If you get it wrong, Bad Things happen!
BTW, the effects of a power cord are much easier to measure than that of fuses. I've seen a power cord rob an amplifier of about 1/3 of its total output power!
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Ralph, how should I interpret this?
>> ^^ Do you understand how power cords are wired? If you get it wrong, Bad Things happen! Interpret is as: Don't mess with rewiring power cords unless you understand local code and know what you are doing! Otherwise the power cord can become deadly as a shock or fire hazard! |
