A couple of further comments regarding the statements at the AH site:
1)As I mentioned in my previous post, it follows from the second of the two statements I quoted that a "typical fuse" provides zero noise rejection. Which sounds right to me! Their first statement I quoted says that their fuse increases "high frequency noise-rejection fifty fold over that of a conventional fuse." It’s worth reflecting upon the fact that 50 times zero is still zero.
2)Regarding their statement about the 10 ohm impedance of their fuse at 10 MHz, a far more effective approach to attenuating 10 MHz noise, as well as noise at other similarly high frequencies, would be to put a suitably chosen ferrite clamp costing a few dollars around the power cord, near the IEC connector on the component. Which is not to say, though, that in a given application there would necessarily be any benefit from doing so.
Personally, I would always much prefer to see a manufacturer say something along the lines of "frankly, we don’t know why it works but it does," than to provide misleading and specious technical explanations.
Best regards,
-- Al
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Geoff, yes, I agree with your post just above. I’ll add that there are practical reasons why a manufacturer might choose not to seek a patent, such as the attorney costs that may be involved. And perhaps also the amount of time that is required to secure a patent, which may exceed the product’s anticipated life cycle.
In general, the usefulness a patent might provide to a prospective purchaser, if any, will result mainly from the information it provides about the product.
Regards,
-- Al
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Hi Frank,
As a point of information, the U.S. Patent and Trademark Office does not verify that an invention that is the subject of a patent application works as claimed. Although they will refuse to grant a patent for an invention that is patently impossible, pun intended :-) A classic example being any form of a perpetual motion machine.
BTW and FWIW, regarding the indication at the AH website of a patent pending for their fuse technology, I had used the search features at uspto.gov to search for both granted patents and patent applications, using various terms relating to the name of the company and its proprietor. My search came up empty-handed.
Best regards,
-- Al
(Licensed but non-practicing patent attorney)
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It almost sounds like you're making some sort of comparison between
aftermarket fuses and perpetual motion machines but maybe I'm reading
too much into your post. Yes, you are reading too much into my post. But thanks for the award :-) Regards, -- Al |
No, I haven’t Geoff, although I haven’t ever looked very thoroughly.
BTW, an improvement of an existing invention can certainly be patentable in many cases. It just has to meet the basic requirements for any patent, namely being new (meaning the improvement has not been done previously); useful (pretty much anything will be considered as meeting this requirement, aside perhaps for something like a substance whose only functionality is causing cancer in humans); and non-obvious to one reasonably skilled in the particular art.
Regards,
-- Al
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Georgelofi 2-7-2017
Moving up in amperage with mains fuses, is unsafe.
Doing this is a very unsafe practice.
It will very likely burn out more than just the fuse.
EG: regulators, rectifiers, or maybe even the transformer.
+ whatever caused the fuse to blow in the first place.
The worst is it could start a fire, and take out your house. On the other hand, though, given the various reports we’ve seen in this thread of SR fuses blowing when they shouldn’t it could be argued that going up one or even two rating increments with SR fuses is likely to result in the fuse having a melting point (as measured in amps squared x seconds) that is **closer** to that of the stock fuse than an SR fuse having the same current rating as the stock fuse. Although admittedly the basis for such a contention is muddled by the fact that some (although by no means all) of the reported false blows have occurred at turn-on, when very brief "inrush" current surges, that are expectable in many designs, may greatly exceed the rating of the stock fuses. In any event, given the lack of meaningful technical data on the SR fuses I don’t think anyone can provide an answer to this question with any kind of certainty, and it is a question about which the opinions of reasonable people (and technically knowledgeable people) can differ IMO. Also, given that some have reported good results with SR fuses that are rated even a bit lower than the ratings of the stock fuses, the answer certainly figures to be equipment dependent. FWIW, my opinion on this question was stated in a post in this thread dated 1-14-2017, near the top of page 64 (if posts are sorted most recent last). Which was to the effect that I personally would have no qualms about going up one or even two rating increments. Regards, -- Al |
Al, your silence is deafening, are you getting splinters?
Hi George, At this point a multitude of opinions and experiences have been stated that are relevant to choosing the current rating of an SR fuse, including opinions from technically knowledgeable people such as you and I. Those reading the thread who intend to try SR fuses can and will form their own decisions as to how to proceed. For those who may be pondering this question, though, I'll add the following question and answer to my previous comments on the matter: Question: Are the protection characteristics of a stock 5 amp fuse, especially the combinations of current and time that would cause it to blow, most closely approximated by an SR Black 5 amp fuse, or by an SR Black 6.3 amp fuse, or by some other SR Black fuse? Answer: We don't know. Best regards, -- Al
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Hi George,
The point to the Q&A in my previous post is that we don’t even know if an SR Black 5 amp fuse should truly be considered to be a 5 amp fuse, as opposed to a 4 amp fuse or something even lower. And the reports we’ve seen from a number of people of blown SR fuses would seem to suggest that one of the latter possibilities could very well be the case, for many if not most or all ratings. Also, fuse derating (the margin between the current rating a designer has chosen for a fuse and the amount of current it conducts under normal conditions) is not a precise science, with designer preferences, the limited number of choices that are imposed by standard rating values, and turn-on inrush currents and other characteristics of the particular design all factoring into it.
So my basic intention is to provide food for thought, rather than advocacy. Although per my various posts on the subject I would not consider it to be an unreasonable course of action for someone who wants to try SR fuses to choose values that are one or even two increments higher than stock, and in the end perhaps avoid wasting several hundred dollars as a result. I respect the fact that your opinion differs, and as I said earlier, given the lack of meaningful technical data on the SR fuses I don’t think anyone can provide an answer to this question with certainty.
Regards,
-- Al
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Oregonpapa 2-27-2017
Joe Williams and the Brit, Al Hibbler, were two more favorites of mine back in the day.
I've always loved Al Hibbler's classic 1955 recording of "Unchained Melody." How anyone could prefer the 1965 recording by the Righteous Brothers, who it seems had the best known and most popular of the many hundreds of recordings of the song that have been released, is absolutely beyond me. A minor correction, though: Al Hibbler was an American. Best regards, -- Al |
Nyame 3-14-2017
I am very disappointed that, as a fully trained Lawyer, you remain silent in the presence of Wolf-Garcia untenable sustained attacks on Oregonpapa and this thread. Nyame, allow me to point out the following statement which I made on 1-24-2017, in a response to one of your posts, which (similarly to your post above) alleged that a post of mine was "convoluted nonsense." Even though that post had been commented upon favorably by members representing all sides of the issue. I have considerable respect for Frank’s system, sonic perceptiveness, and sincerity. Nothing I have said (or thought) at any point in this thread has been in any way inconsistent with that statement. Regards, -- Al |
While the opinions I have expressed during the course of this thread do not coincide with those representing either extreme of the belief spectrum, I’ll say that I believe George has raised an interesting point about degradation of the fuse element over time, as a result of repeated turn-on surges or other use-related factors. That possibility not having been stated previously in the thread, as far as I can recall, and I suppose it might account for perceived improvements with upgraded fuses in some if not many cases.
Frank and others mentioned significant further improvements when upgrading from "near new" SR Red to SR Black fuses, and I don’t doubt their perceptions. But perhaps the several reports we’ve seen in the thread of SR fuses being more prone to blow in some applications than stock fuses signify that the degradation/aging effect George has referred to occurs more quickly with those fuses than with typical stock fuses. Perhaps almost instantly in some applications, to some degree, given that some of the false blows have been reported to occur immediately.
Just a thought, which at this point I suppose can’t be ruled out as being a factor in some if not many cases.
Regards,
-- Al
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Why would anyone put a crappy fuse in such a vital area, knowing it’s going to fail long before (if ever) required? It would also affect performance long before it ever blows....
These boutique fuses seem to address the failings of cheap fuses by a
more robust construction with attention paid to the rigors a fuse goes
through when doing it's job....
Precisely. Which raises the question of why we have seen multiple reports in this thread of SR fuses blowing when they shouldn’t, and perhaps in many cases having to be chosen at current ratings higher than stock. Regards, -- Al |
Mac48025 3-14-2017
Are the SR fuses blowing for no reason? I have 6 SR black fuses with the same values as the stock fuses they replaced without incident. Might the issue be one that only applied to the early fuses? Mac48025, after briefly making use of the "Find" function that is provided in the Firefox browser I use, using the terms "blew" and "fail," I believe that the most recent reports of SR fuse failures were in posts by members "whitestix" on 1-22-2017, "fynnegan" on 1-14-2017, "fleschler" on 12-21-2016, "sns" on 12-10-2016, "mtseymour" on 11-10-2016, and "dlcockrum" on 11-5-2016." Some of these reports involved SR Reds, and some involved SR Blacks. Some of the reported failures occurred instantly, and some after a period of time. Also, Wolfie had reported that a couple of the SR fuses he tried in various components in his system had blown, as did at least several members who posted earlier in the thread. FWIW, my guess as to why some have experienced these failures and others have not relates to differences in turn-on surge currents (referred to by EEs as "inrush currents") among different component designs, and perhaps also to differences in susceptibility to failure among SR fuses having different current ratings and/or different fast blow/slow blow ratings. Also, regarding the correction that you subsequently made to your post that I quoted from, FYI you can edit a post during the first 30 minutes after it is submitted. Click on the gear shaped icon at the upper right corner of the post, and click "edit." Best regards, -- Al |
Why not just go for $0.10 if it doesn't make a difference?
I have never said it won't make a difference. In fact I have said the opposite many times, in this and other fuse-related threads. For example, see the summary of my technically based opinions on the matter that is presented in my post dated 1-20-2017 in this thread. Regards, -- Al |
For those considering replacing a stock fuse with an inexpensive new fuse, I suggest purchasing either a Littelfuse or an Eaton/Cooper Bussmann fuse. A good source is industrial distributor Digikey, which has no minimum order requirement or handling fee: http://www.digikey.com/products/en/circuit-protection/fuses/139They do cost more than $0.10, though. More like a dollar to two :-) Regards, -- Al |
Geoffkait 3-20-2017
I don’t think it’s correct to say it’s an open forum per se. Most other
audio forums don’t allow politics, religion or other hot topics on audio
forums but instead have a place where people can go and bash away at
each other.
+1. And of course that is also often the case at non-audio forums. For example I participate in a forum for computer enthusiasts and builders, which among many other sub-forums has one called "heated debates." That is where discussions of politics, religion, and other subjects that are just about certain to result in ugly off-topic exchanges are relegated. And perhaps that is where the line in the sand that Charles referred to should be drawn. When a topic is BOTH particularly controversial AND not germane to the subject matter of the forum. Regards, -- Al |
Marqmike, thanks very much for the nice words.
Regarding the appropriateness of political discussion at this forum, like JonD I was surprised at the controversy that resulted from his extremely polite and respectful request. Which to Frank's credit was received amicably and readily agreed with by him, as the OP.
In the past I have seen many requests in other threads for members to avoid bringing politics (and also religion) into the discussion. Jon's request was easily the most respectful and polite request of that kind that I can recall.
And I agree that such discussions have no place here. Although I suppose that arguing about what to argue about is preferable to arguing about such subject matter itself :-)
Regards,
-- Al
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Tommylion, I don’t know which release of the Heifetz/Reiner/CSO recording of the Brahms Violin Concerto you listened to, but can you or anyone else here comment on the Analog Productions/Acoustic Sounds reissue on LP?
Regards,
-- Al
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Tommylion 3-22-2017
Just finished listening to Jascha Heifetz playing Brahm’s Violin Concerto with Fritz Reiner and the Chicago Symphony Orchestra
Amazing! It’s moments like these where all this "audiofool" stuff really pays off.
Must have been wonderful! Brahms is one of my favorite composers (my favorite symphony among those that have ever been written by any composer is probably his No. 1), and Heifetz/Reiner/CSO is certainly an exceptionally distinguished combo. I believe that recording dates from the 1950s. I have several other versions, but not that one. I’ll have to add it to my "buy" list. Regards, -- Al |
Thanks, Geoff! I'll try to find it on vinyl, as my Tandberg 3004 cassette deck needs repair (which I've been procrastinating on, as the repair will most likely be quite expensive).
Regards,
-- Al
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Thanks Frank. I hadn't previously known of Erica Morini. For those who may be interested in but unfamiliar with the Brahms Violin Concerto, here is a relatively recent live performance by the great Itzhak Perlman as soloist, with Daniel Barenboim conducting the Berlin Philharmonic: https://www.youtube.com/watch?v=jM12fUAlZtURegards, -- Al |
Charles, you have been and are the solid and reasonable rock for this thread.
As is the case in many a thread. George (Jetter), your 13 point summary (as amended) gets my nomination for best post of the month. Perhaps the year! Best regards, -- Al |
Nonoise 3-25-2017
I posted ’auxinput’s’ contribution from another thread earlier about how the signal is about 98% A/C voltage and no one has shot that down yet. Glossed over maybe, but not disputed.
Taking that into consideration (at the very least), doesn’t it leave open the ’weak link’ aspect of the fuse? The salient paragraph of Auxinput’s post, which you quoted in this thread on 3-9-2017, was: In a power amp circuit, the output transistors have to create massive gain (turning a 1V input into something like 15-100 watts or more). It has to use the A/C power coming in to create this voltage, so your signal is actually something like 98% A/C voltage. Obviously just about all of the power that is put out by an amplifier (or any other AC-powered component) is **derived** from the AC power that is provided to the component. However, saying that does not provide any kind of meaningful explanation as to how an AC mains fuse may exert an audibly significant effect on the output signal of the component, given all of the intervening circuitry that is present, that is (or at least should be) designed to minimize the sensitivity of that output signal to differences in the incoming AC. And it certainly does not provide such an explanation that would stand up when analyzed quantitatively, or that can even be analyzed quantitatively. Or (as I’ve said in earlier posts) that would explain the high degree of consistency of the reported benefits, among components that are completely different in design, that perform completely different functions, that are used in very different systems, and that are powered by AC having very different voltage and noise characteristics. Simply asserting that a fuse may be a weak link in some way is not an explanation that would be viewed as meaningful by the court of electrical engineering. Which is not to say that a ruling by that court is definitive. It is to say, however, that the proffered explanation is not definitive either, or even meaningful. Best regards, -- Al |
Thanks, Nonoise!
Best regards,
-- Al
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Mac48025, I have said on multiple occasions that I don’t doubt that a fuse can make a difference in many cases. With that opinion being based in large part on the many user experiences that have been reported here. Beyond that, my views were summarized in my post in this thread dated 1-20-2017, and I can’t offer anything more in answer to your question.
Best regards,
-- Al
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Charles1dad 3-27-2017
Yes my expectation would be that a 119.00 dollar product should be superior to the 9.00 dollar product or why else would you spend the extra 110.00. What I recognize is that you don’t know with any certainty until you actually compare via listening. Which brings to mind one of the reasons the lack of a good technical understanding of how a product "works" may be significant. Without such an understanding, or at least a basis for confidence that the designers of the product have such an understanding (which would seem doubtful if how the product "works" cannot be either fully explained or fully predicted based on generally recognized science), there would seem to be no basis for anyone (including the designers) to accurately predict the point of demarcation between optimization of a given parameter or design characteristic of the product and what may be overkill of that parameter or design characteristic, which will accomplish nothing in most or all applications.
Therefore, IMO, it can be expected that what may in many cases be a significant driver of the cost of expensive tweaks or other products whose principles of operation are not thoroughly understood (in a quantitative manner, at least) is overkill of some or all of their design parameters and characteristics, which will accomplish nothing in most or all applications. Or that may make a difference in some applications, but a difference that is unpredictable, and may even be for the worse from a subjective standpoint.
That, IMO, being a significant contributor to the loose correlation between price and performance that many audiophiles have reported in various contexts here and elsewhere.
I agree with Charles’ second sentence that I quoted, of course.
Best regards, -- Al
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That was certainly a talented and very special cast on SNL in the days when Belushi was there. Gilda was my favorite, although they were all great.
Best regards,
-- Al
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Geoffkait 3-28-2017
... most or almost all observable phenomena CAN be explained by current scientific laws or facts. What might be difficult for one person to explain might be a snap for someone else. +1. A good audio-related example of that can be found in the current thread entitled "Most Important, Unloved Cable," in which several people reported that significant sonic improvements resulted from upgrading ethernet cables that are used in their systems. With the upgrades in most cases being very inexpensive. A couple of posters, including one who deals with ethernet networking professionally, dismissed that as preposterous, and undoubtedly the result of expectation bias. But for someone who happens to have the right background (me), it was a snap to explain those results. And to explain them in a manner, as I put it in that thread, that is "well within the bounds of established science and engineering." See my post in that thread dated yesterday, 3-27-2017. BTW, in saying this my intent is certainly not to toot my own horn, but simply to provide a specific audio-related example supporting your comment. Regards, -- Al |
Wolf_Garcia 3-29-2017
I’ve met Dennis Had who is a former and current world class designer, and a brilliant no nonsense guy who is fun to talk to and seems to know more than the average forum knucklehead could ever understand about circuits and sound. FWIW, I think most would agree that if the words "former and current" had simply been omitted this sentence would stand as stated, regardless of one’s opinion of the Inspire amps. If a designer has a history of producing multiple designs that can reasonably be considered to be world class, but at other times has produced designs that are less than stellar, he is still a world class designer IMO. Especially if those other designs are at much lower price points than his main body of work. Best regards, -- Al |
Good suggestions by Charles, as usual. A couple of caveats, though, regarding the First Watt F6 and F7.
Their gain is particularly low for a power amplifier, at only 14 db. That will be problematic in some applications, especially if vinyl sources are being used and line stage gain is low. Also, the F7 has an input impedance of only 10K, which will be a problem for many tube preamps.
Basically, I would view the Dynamo as being more versatile than the F6 and F7 in terms of compatibility with upstream components. While I would expect the F6 and F7 to have greater versatility than the Dynamo with respect to speaker compatibility, due to their greater power capability and also their presumably much lower output impedance. With the S.I.T. amps being more comparable to the Dynamo in the respects I've mentioned than to the F6 and F7.
Best regards,
-- Al
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Hello Kalali,
"3AG" is not a current rating. It defines the fuse as being glass and having a physical size of 6.3 x 32 mm (1/4 x 1-1/4 inches).
Beyond that, I have no knowledge of what the MMG may require.
Good luck. Regards,
-- Al
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As for the 100 hrs of breakin, does music actually have to be playing, or is leaving the equipment on enough?
The AC current drawn by a preamp will be essentially the same regardless of whether or not music is being played, as long as the preamp is in an operational mode as opposed to a standby mode. The AC current drawn by a CDP will increase somewhat when the transport is spinning a disc, but almost certainly by an amount that is too small to matter, IMO. So assuming that the fuses you replaced in those components are AC mains fuses there should be no need to play music to break them in. Regards, -- Al |
Regarding polarity switches, a point to keep in mind is that when the position of the switch is changed not only is polarity being changed, but the circuit configuration of the component which provides the switch is also being changed. That in itself could conceivably have audible consequences, to a greater or lesser degree depending on the specific design. I would expect that to be unlikely to be an issue in the case of a fully balanced design such as Frank’s ARC line stage, since in a fully balanced design a polarity reversal can be accomplished by simply interchanging two internal connections. However in a design having a single-ended internal signal path changes involving the configuration of active circuitry would probably be necessary. Oregonpapa 4-13-2017
Here’s another one that I dug out of the vault last night. If you have it, play cut #14 and crank up the volume. Its a good test of a system’s dynamics and the ability to "hold together" while blowing the walls down ... not to mention that its great music a well. :-)
http://www.ebay.com/itm/Antal-Dor-ti-Stravinsky-The-Firebird-etc-Antal-Dorati-CD-5LVG-/302233218987?... Thanks, Frank. I have that recording, on a CD having a release date of 1991, rather than on the 2004 SACD shown at the link you provided. Very impressive, as I recall, although somehow I haven’t listened to it in quite a few years.
One of my all-time favorite recordings of any work is the LP I have of Stravinsky’s Firebird Suite (as opposed to the complete ballet that is on the recording you referred to), Robert Shaw conducting the Atlanta Symphony Orchestra, on Telarc. A digitized version of the LP can be found here: https://archive.org/details/StravinskyTheFirebirdborodinPrinceIgor-Telarc-Vinyl24-bit And it can be found in CD form at the following link. I see from the review comments, btw, that I’m not alone in liking it. It’s great music, as you indicated about the complete ballet, and the performance by Shaw and the orchestra is excellent as well.
https://www.amazon.com/Stravinsky-Firebird-Borodin-Music-Prince/dp/B000003CSF And speaking of dynamics, it is absolutely stupendous in that regard, even relative to the exceptional dynamic range that is found on many other early Telarc releases. It so happens that I have on my computer the same Sound Forge audio editing program that is indicated at the archive.org link (above) as having been used to create the digital files that are provided there. Using that program to examine the waveforms in those files I have found that the difference in volume between the notes at the end of the “Berceuse,” at around 17:20, and the concluding note at the end of the work, is around 60 dB! Meaning that the amplifier has to put out around 1,000,000 times as much power to reproduce the concluding note as to reproduce the softest notes. That is consistent, btw, with SPL measurements I have made at my listening position, those being about 105 dB on the concluding note, and less than 50 dB on the softest notes. (My meter can’t measure below 50 dB). Best regards,
-- Al
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All best wishes, Frank, for a problem-free surgery and a speedy recovery. My impression is that heart surgery these days is a much more exact science and much more predictable than many other kinds of surgery.
Looking forward to your return to the forum in the not very distant future.
Best,
-- Al
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First, kudos to Aeoluskratos for a sincere and nicely done first post. Second, I don’t wish to rehash the subject of fuse directionality, which has been debated ad nauseam in this thread. But I want to correct a misstatement of fact: Geoffkait 5-10-2017
It’s not really "electricity" that is alternating, it’s the current that’s alternating. The voltage is not alternating. Otherwise they’d call it AV. Both the voltage and the current alternate in AC. That follows from the fact that per Ohm’s Law, which applies to resistive loads, voltage and current are directly proportional to each other. (And for a capacitive load current is proportional to the rate of change of voltage, and vice versa for an inductive load, and all of those quantities also alternate in the case of AC). That can be easily seen on an oscilloscope, where the vertical axis of the graph that is displayed corresponds to voltage and the horizontal axis corresponds to time. AC will look like a close approximation of a sine wave, swinging both positively and negatively, above and below zero volts. Regards, -- Al |
On **numerous** occasions earlier in this thread and in several other fuse-related threads I as well as several respected designers of highly regarded audio electronics have explained why the measurements reported in the HiFi Tuning paper are not supportive of claims that fuses are inherently directional. One of many such statements was this one by Roger Modjeski of Music Reference and RAM Tube Works, which I quoted in this thread on 10-28-2016: Has anyone considered what portion of the total resistance the fuse contributes to the whole of the circuit in which it is inserted?
From the Tuning Fuse data sheet their 2 amp slow blow 5x20 fuse has a resistance of 24.077 milliohms in one direction and 24.115 in the other direction and 26.257 in the holder. If a butterfly flew by while the measurements were taking place we might see a bigger difference than the 0.038 milliohm difference in direction. Of course it might depend on which direction the butterfly was flying. But never mind, the direction measurements were made with DC and we are using these fuses in AC circuits. Perhaps if the butterfly flies clockwise vs counterclockwise there will be a difference.
Sorry I just had to put that in to keep up with all the humor that has been presented here.
[Note: 0.038 milliohms is 0.000038 ohms]
In another post in this thread, dated 10-7-2016, I said as follows: Regarding the measurements described in the HFT paper ... which purport to support the notion of fuse directionality:
IMO those numbers are so miniscule as to be:
(a)Laughable.
(b)Very possibly attributable to changes in the voltage of the battery in the measurement meter, from measurement to measurement (each measurement imposing a slight drain on the battery), and from minute to minute. Or if the meter was AC powered, to the very slight differences in AC line voltage that may occur from minute to minute, as various loads are turned on and off at nearby locations.
(c)Very possibly attributable to differences in contact pressure and contact area between the meter’s probe tips and the contacts on the fuse. The paper presents separate measurements of fuse resistance as measured in a fuseholder (for just one direction), indicating that the direction-related measurements were performed by touching the meter leads directly to the contacts on the fuse.
(d)Perhaps even contributed to by differences in the resistance of the measurer’s body, that would have been paralleled with the resistance of the fuse if he or she had fingers on the probe tips and/or the fuse contacts while the measurements were being taken.
(e)If Geoff’s comments about all wires being significantly directional are to be believed, then these differences would be totally swamped by both the resistances and the alleged direction-related resistance differences of the vastly longer associated wiring. In the case of mains fuses, that would include the power transformer and the power wiring in the component, as well as the power cord and the AC wiring in and outside of the house. All of which is NOT to say that the direction-related sonic differences which many have reported are the result of extraneous variables such as differences in equipment warmup state, or misperception, expectation bias, etc. I don’t doubt that many of the reports are accurate. But another distinguished designer, Ralph Karsten of Atma-Sphere, has explained why those differences would have occurred, and has indicated that he has verified his claims with experimental measurements. In a post in this thread dated 10-28-2016 I quoted the following comment he had made in a different fuse-related thread: Ralph Karsten of Atma-Sphere: … Fuses are inherently incapable of having directionality in any way whatsoever. … 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…. 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.
Yet despite all that, and despite similar comments about the HiFi Tuning measurements that have been provided in numerous other posts going all the way back to the "Fuses that Matter" thread that began in 2012, Geoff continues to assert that the HiFi Tuning measurements support the notion that fuses are inherently directional. Regards, -- Al |
TheAudioTweak 5-21-2017
Hanging on this hair thin element is an 8 gauge power cord ..what kinda battle of scale and competing forces is that one. Just a projected image..Tom That is a good point. And the resistance of a typical mains fuse will in fact be a bit higher than the resistance of an 8 gauge power cord of typical length. But to provide some perspective from a quantitative standpoint: The combined resistance of the hot and neutral conductors of a six foot 8 gauge power cord is about 0.0075 ohms. A 6.3 x 32 mm Littelfuse series 313 glass fuse rated at 5 amps and 250 volts has a specified "cold" resistance (i.e., its resistance when conducting negligible current) of 0.0214 ohms. The resistance of the fuse will presumably rise slightly when conducting a typical amount of current, say 2 amps for a fuse having a 5 amp rating. So let’s call its resistance 0.04 ohms. (That would seem to be a reasonable assumption given that 0.04 ohms is almost exactly the same value that is indicated in the HiFi Tuning paper for a "standard" 5 amp 6.3 x 32 mm ceramic fuse when conducting 3 amps). 0.04 ohms x 2 amps results in a voltage drop of 0.08 volts. The 0.0075 ohm resistance of the 8 gauge power cord x 2 amps results in a voltage drop of 0.015 volts, substantially less than the voltage drop of the fuse. Therefore if the incoming line voltage is 120 volts, the 8 gauge power cord would reduce the voltage seen by the component to 119.985 volts. The Littelfuse would reduce it further to 119.905 volts. Will the overall reduction of approximately 0.1 volts have audible consequences? It seems unlikely, considering that at most locations line voltages probably fluctuate a good deal more than that from time to time, especially between daytime and nighttime. But I suppose it could conceivably be marginally significant in some cases, especially if the particular component being powered does not have regulated DC power supplies (as in the case of most power amplifiers). On the other hand, though, **even if** the 0.1 volt drop does have audible consequences, if the line voltage at the particular location happens to be higher than the voltage the component was designed to sound best at (presumably 120 volts in the case of most components that are intended to be used in the USA and other 120 volt countries), that voltage loss might actually be advantageous. And the somewhat lower resistance of the HiFi Tuning 6.3 x 32 mm 5 amp Gold Cryo fuse (about 0.013 ohms when conducting 3 amps, as indicated in their comparison test paper) might actually be disadvantageous. Regards, -- Al |
Al,
Thanks for your knowledge and response!
The answer to find a better fuse might be in some dynamic testing method which you may have some knowledge of rather than just the standard heat rise and current capacity that I have read about.
Tom Thank you, Tom. I have no particular knowledge of dynamic testing methods which may be applicable to fuses. And the very comprehensive datasheet (linked here) for the Littelfuse series 313 fuses, one of which I used as an example in my previous post, makes no mention of any such tests. By the way, FWIW that document does indicate that those fuses are compliant with various MIL-STDs (military standards) for vibration, as well as for thermal shock, humidity, and salt spray. Although of course those standards are intended to assure reliability under adverse conditions, not to assure good sonics in an audio system. But regarding dynamic behavior, as indicated in the example in my previous post the resistance of a fuse will of course fluctuate somewhat in response to fluctuations in the current it is conducting. And it wouldn’t surprise me if those fluctuations had audible consequences in the case of a speaker fuse, or a fuse used in the output stage of a power amplifier or integrated amplifier. Depending in part on how much the designer is able to "derate" the fuse in the particular application (meaning how much margin is provided between the current rating of the fuse and the actual amount of current it conducts in the particular application). Conceivably also in the case of a mains fuse in a class AB or class D power amplifier or integrated amplifier (most of which do not have voltage regulated DC supplies for their output stages). But not in the case of virtually all other components, since in virtually all other applications (including preamps, DACs, source components, and mains fuses in class A amplifiers) the current conducted by a fuse is essentially constant all the time. One further point, btw, to add perspective to the 0.08 volt drop in the resistance of the fuse I used as an example in my previous post. It’s worth noting that in the USA AC line voltages are considered to be in spec if they are anywhere within a 12 volt range, between 114 and 126 volts at the circuit breaker panel. Regards, -- Al |
Great to see you back here, Mapman. Many here have noticed your absence in the past few months. Hope all is going ok for you and the family. As well as for Frank, of course.
Best regards,
-- Al
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Thank you, Kenny (Kdude66). I’ve enjoyed your posts in the Tekton Double Impact thread. Geoffkait 5-26-2017
Ignore the AV just like the AC when it’s traveling in the direction toward the wall outlet. You can’t hear what’s headed toward the wall outlet, only what’s headed toward the speakers. That’s why fuses are directional in both DC circuits and AC circuits. CASE CLOSED. On the other hand, though, an instructive experiment might be to install a diode having a suitable current rating in place of the mains fuse of a component. Connecting it such that it would allow current in the direction of the component, but would block current in the direction of the wall outlet. Chances are nothing much at all would be heard in most cases. Before as well as after the component’s power transformer burns out due to the resulting DC offset. Regards, -- Al |
Yes, great news indeed, Frank. Thanks for the update, and continued best wishes as you proceed with your recovery.
Also, Dave, good to see you back here lately.
Best regards,
-- Al
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Tommylion, I have long considered Brahms' First to be my all-time no. 1 favorite symphony. I don't have the Klemperer, which I understand to be magnificent. But among the various versions I have my favorite is the performance by Jascha Horenstein and the London Symphony, recorded in 1962 and masterfully reissued on a Chesky CD. It is out of print but is available used from various sellers. Performance and sonics are both amazing! Also, Toscanini's remarkable 1940 performance can be listened to and/or downloaded and burned to CD (which I've done) here. The performance is sufficiently captivating that the primitive sonics probably won't matter. They didn't for me, at least. Regards, -- Al |
Tommylion, thanks. That's definitely a tweak that makes sense from a technical standpoint, IMO. The degree to which it may help will of course vary depending on the design of the specific component. Also, in cases where unused digital outputs on BNC connectors are involved, something like this should do the trick: https://www.bhphotovideo.com/c/product/167156-REG/Comprehensive_B_TM_B_TM_BNC_Terminator.htmlRegarding unused S/PDIF or AES/EBU digital inputs, those presumably already have a termination, internally within the component. Regards, -- Al |
Hi Dave,
The part that I linked to has a 75 ohm resistor built into it. And since it is intended for use in video applications (I have used it for that kind of purpose) I would expect the resistor that has been chosen to be suitable for use in terminating the RF frequencies that are present in digital audio signals.
Best regards,
-- Al
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Wolf_Garcia 9-21-2017
Anybody able to locate the above mentioned "UEF Tech" patent? I'd be interested in whatever the heck THAT says.
Wolfie, I did a search at the U.S. Patent Office website (uspto.gov) of both granted patents and patent applications that have been filed, using a great many relevant search terms. I found nothing relevant to SR or any of its products, or to UEF (Uniform Energy Field) technology specifically. Best regards, -- Al (Licensed but non-practicing patent attorney)
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Thank you, Tom (Theaudiotweak). For the record, though, his name is spelled "Denney," not "Denny." That misspelling has also been made by a number of others during the course of this thread.
The only mention of SR or any of its products I found in my search of granted patents and patent applications was a very brief mention in the text of two patents involving dielectric bias techniques that had been jointly granted in 2006 and 2011 to Bill Low and Richard Vandersteen. But neither those patents nor anything else I found made reference to any patents granted to or applied for by SR or Mr. Denney.
Regards,
-- Al
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Thank you, Tom (Theaudiotweak). Based on your input I was able to find the patents listed here that have been granted to Mr. Denney, under his own name. However, as far as I can see none of them appear to be related to fuses. Regards, -- Al
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Rauliruegas 9-22-2017
I decided to do it thinking that if the power line now is fully
regulated and bullet proff with surge protrectors then the item input
fuses are just out of the " equation ", we don't need it any more.
Nonoise 9-22-2017
If someone has, let's say, whole house surge protection (i.e. at the
fuse box) then it would negate the need for fuses, period. The same
would go for anyone with surge protection for their components.
Raul & Nonoise, with due respect I'm surprised that the two of you would make such statements, as if what you have described has no downside in terms of safety. It should not be necessary for me to explain why the approach you have described amounts to a significant safety risk, not to mention a risk to your investment in the equipment, so I won't take the time to do so. Regards, -- Al
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@rauliruegas & @nonoise, thank you for your gracious and reasonable responses to my previous post. To some of the other recent posters: Regarding "I am there" vs. "they are here," the following thread from 2010 may be of interest, in which there was an extensive and particularly intelligent discussion of exactly that question: https://forum.audiogon.com/discussions/quot-they-are-here-quot-vs-quot-you-are-there-quot@theaudiotweak, Tom, am I correct in inferring from some of your recent posts that you consider the patent question about the Blue fuse to have been answered? If so, can you explain further? The Blue’s description at the SR website states in part as follows: The new SR BLUE Quantum Fuse was developed over a two year period and represents our most advanced UEF Technology to date. At its heart is a completely new UEF / Graphene coating that delivers a dramatic increase in resolution and holographic realism over SR Black....
... At Synergistic Research we’ve isolated key factors that affect how electricity propagates by changing the behavior of electrons through Inductive Quantum Coupling methods we collectively call UEF Tech. In fact, UEF Tech is so powerful even an electrical chain several miles long is fundimentally [sic] improved with nothing more than a single fuse engineered with our patented UEF Technology. Yet none of the four patents we have determined to have been granted to Mr. Denney make any mention of fuses, UEF (Uniform Energy Field) technology, or Inductive Quantum Coupling. Regards, -- Al |
Tom (Theaudiotweak), thank you for the comprehensive response to my previous post.
Best regards,
-- Al
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