Audiophile Fuses

I ask this question out of wanting to understand. Not trying to start anything, just trying to understand.
How can a fuse possibly make a difference in SQ?
It really can only change sound if it alters current/voltage by adding/reducing resistance.
I understand my system might suck so bad I might not be able to hear the difference, but it does respond very audibly to very minute changes.
I have bypassed my fuses completely in my maggies and didn't hear any difference at all. Maybe I should try again now that it is considerably dialed in than before.
Are they just salting the sound to your flavor.
The son of an EE in me says if it changes the sound there is a problem in the design.
Help me to understand with something other than, "Trust me you have to try it"
The only thing I can see is they are loading the system, which they should not do at all.
Asking for a friend...
 
SR blue is out. Feel like this fuse resort to cheap trick. Kill all musicality. Not suitable for hi-end system.
 
Audiocrack has asked a couple of times if I'd report on the Audio Magic SHD Ultimate beeswax, in light of my also having tried the SR Blue (in two different locations). While I wouldn't let the SR Blue near my system again, to be fair and balanced (LOL) it has some qualities that are a substantial improvement over the SR Black and have obvious appeal (along with its price, relative to the Ultimate). My first reaction to it in the PS Audio DirectStream dac and then their P10 power regenerator was how much it made the music swing; it's got PRaT galore! It's also brings a very quiet background, as many have noted, which adds a sense of considerable transparency and expansiveness. Tonal/timbral accuracy, however, along with a certain dryness and somewhat recessed soundstage, were another matter, which led me to move on.

The effects of the Ultimate beeswax, which I first put in the DS, and now also in the P10, are very different, and perhaps will be most appealing to a different kind of listener. What immediately stood out to me were two things: much greater tonal/timbral accuracy - e.g., pianos sounded like pianos, voices like voices - and, well, the word "articulate" kept and keeps coming to mind. One actually hears each note in its fullness, and between notes, as well as "all the way around” each instrument on decent recordings, i.e., the overtones and undertones and resonances, especially in smaller ensembles. There's a substantial sense of each note and instrument having body, and with it tonal clarity and delicateness. Bass comes across more substantive and precise into the lower registers (e.g., acoustic bass), although I won't be able to judge fully until I get a pair of JL Audio subs set up. Liquid (or almost so) is a term that comes to mind sometimes. Other times, rich. The soundstage is relatively broad and in my system at least, up close to the speaker horizontal, which is my preference. Image stability is very decent. One other result of it bringing out so much more in recordings is that a lot of poorer recordings and mp3’s sound better than previously heard (but not by eliminating flaws, such as by rolling off the highs).

Jerry of Audio Magic refers to the Ultimate as tonally the most natural sounding fuse he's developed. I would say yes, with the caveat that "natural" means vastly different things to different developers and listeners. So I will say that it is modestly warm, easily more so than the SR Blue, and has a relaxed smoothness and delicatness to its articulateness, feeling alive in a very different and I find more substantial way than the Blue. To me, the SR Blue is about entertainment, the Ultimate about music. Without looking to do so, I find myself listening to songs and CDs all the way through now that I had previously only been able to take in smaller doses.

Is it as quiet as the SR Blue? Probably not quite. Does it swing like the SR Blue? That's an interesting question, which as I listened to the Ultimate made me reflect on my listening experience. The Ultimate brings out so much in recordings that the music actually feels slow some of the time. I'm not saying that it is, and I’m not having any problem being drawn in, whatever the tempo. Rather, it's a matter of balance: our perceptions emerge from the totality of what's presented, and the Ultimate brings out a lot more than the Blue, which renders PRaT only one among several characteristics. In that sense, the Ultimate often gives the feeling of having elevated my system to the next level, rather than just improving it.

System used: PS Audio PowerBase and P10, Oppo 203 modified, DS dac, ATC SCM19A active speakers (w/ SR Blacks currently), cable box/TV, PS Audio AC-12 power cords and MG Audio Design AG2/S2 IC, Furutech NCR(R) outlet.

P.S. My view on fuses is that they are a special kind of and extension of the power cord, the passage from the latter to each component's power supply. As with power cords, the better the fuse, the better the "material" the component's power supply and thus the rest of its innards have to work with.


Dear highstream,

Thank you for your very well-written and understandable comparison of these fuses. I truly enjoyed reading the report.

But I have received a complaint from the Hyperbole Police. They have requested that I ask you to confirm or explain some of the statements in your post.

I am sure you are correct that the fuses sound different, but are you certain the comments in italics are correct, measured, proportional and not exaggerated? Thank you!

“. . . Audio Magic SHD Ultimate beeswax . . . substantial improvement over the SR Black . . . how much it made the music swing; it's got PRaT galore! It's also brings a very quiet background. . . which adds a sense of considerable transparency and expansiveness. . . .”

The effects of the Ultimate beeswax . . . much greater tonal/timbral accuracy - e.g., pianos sounded like pianos, voices like voices . . . Bass comes across more substantive and precise . . . Image stability is very decent. . . . bringing out so much more in recordings . . .”

“. . . The Ultimate brings out so much in recordings . . . and the Ultimate brings out a lot more than the Blue . . . the Ultimate often gives the feeling of having elevated my system to the next level . . ."

In addition, before you changed fuses, did pianos not sound like pianos? If not, what did they sound like?

Did voices not sound like voices? If not, what did they sound like?
 
If fuses are such a big deal , then a hardcore audiophile should go without :D
I know its a bit risky regarding equipment but the sonic bliss ought to make up for it :)

If the fire services did an investigation after a house fire your house insurance will probably be voided.
 
Thanks to AK

"At low frequencies the audio signal can heat up and cool down the fuse element within a single cycle, causing the resistance of the fuse to vary as a function of the signal amplitude. This leads to distortion because the attenuation of the fuse resistance against the load impedance changes as a function of signal swing [5]. Fuses are often undersized with respect to the peak audio current they may be called on to pass, recognizing that a smaller fuse will provide relatively more protection and that with normal audio signals, such high currents are brief events much shorter than the time constant of the fuse element. The cold resistance of a 2-A 3AG fuse was measured to be 78 m?, while its resistance when passing 2-A DC was 113 m?. This represents a 45% increase in fuse resistance.

The distortion of a fuse can be measured by looking at the voltage across the fuse with a sinusoidal signal current passing through it. The fuse under test is put in the ground leg of an 8-? load resistor so that the signal voltage across the fuse can be easily analyzed. This technique largely takes the distortion of the driving source out of the picture. Figure 13.4a is a plot of fuse distortion versus frequency when a 2-A fast-blow 3AG fuse is passing a 2-A RMS sine wave signal. As expected, fuse distortion increases dramatically at low frequencies. Signal voltage across the fuse was 250 mV. Amplifier THD (due to the fuse) is calculated by normalizing the fuse distortion voltage to the amplifier output voltage. The resulting amplifier distortion is shown in Figure 13.4b. Amplifier distortion is lower than fuse distortion by a factor of 64 because of the small voltage across the fuse compared to the total signal voltage. At 20 Hz, amplifier distortion due to the fuse is calculated to be 0.0033%."

Other relevant papers:

Amplifier-Loudspeaker Interfacing
Author: Greiner, Richard A.
Affiliation: Department of Electrical Engineering, University of Wisconsin, Madison, WI,
JAES Volume 28 Issue 5 pp. 310-315; May 1980
Publication Date: May 1, 1980


"Ideally the fuses used in the output current circuit would be linear resistors as well. However, since Fig. 4. Reproduction of an oscilloscope trace showing that they have to get hot (and melt) to burn out, they are actually out cycle for a fuse with a 20-Hz signal large enough to cause nonlinear elements in the output circuit. If fuses are to be burnout in about 0.8 s.

The substantial change in the slope of the V-I curve shown indicates a large resistance change with heating useful, they must blow out when the system is used at some of the fuse element. specified power level over the maximum desired. Typically, a fuse will increase in resistance to about 3 or 4 times its cold value just short of burnout. At 60% of full load it bursts just short of fuse burnout.

Typical measured modulawill increase to about twice its cold value. A typical fuse tion of a high-frequency signal when pulsed with tone blow-out cycle is shown in Fig. 4. The resistance change bursts that are set at 60% of burnout are shown in Fig. 5. per cycle is clearly evident. The calculations and measure- This figure shows the oscilloscope trace of a 5-kHz signal merits of this section show some possible problems with modulated by 20-Hz tone bursts. The tone bursts have been distortion caused by these changes in the fuse during normal filtered out to show only the 5-kHz modulated signal.

The program reproduction, heating and cooling cycle of the fuse is clearly visible. The Using the simple circuit of Fig. 3, it can be shown that for time constants of typical fuses are such that this heat, and a typical regular speed fuse, of the tubular type, the distortion- consequently resistance, cycling can take place for normal distortion produced could reach the values shown in Table 6. musical beats at low frequencies. To minimize interaction These figures represent intermodulation distortion for any of this type across the frequency spectrum, it would seem frequency when the output circuit is pulsed with power wise to provide separate fuses for each frequency range of a multiway system.

Fast blow fuses are worse than regular fuses since they change temperature 10 times more quickly. There is no solution to this problem except over fusing or putting inside of a feedback loop. This can be done, of course, by putting the using fuses at all, unless the fuses are included within the fuses in the power supply bus or even within the normal -- feedback loop."


20180328_131109.jpg
 
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Dear highstream,

Thank you for your very well-written and understandable comparison of these fuses. I truly enjoyed reading the report.

But I have received a complaint from the Hyperbole Police. They have requested that I ask you to confirm or explain some of the statements in your post.

I am sure you are correct that the fuses sound different, but are you certain the comments in italics are correct, measured, proportional and not exaggerated? Thank you!

“. . . Audio Magic SHD Ultimate beeswax . . . substantial improvement over the SR Black . . . how much it made the music swing; it's got PRaT galore! It's also brings a very quiet background. . . which adds a sense of considerable transparency and expansiveness. . . .”

The effects of the Ultimate beeswax . . . much greater tonal/timbral accuracy - e.g., pianos sounded like pianos, voices like voices . . . Bass comes across more substantive and precise . . . Image stability is very decent. . . . bringing out so much more in recordings . . .”

“. . . The Ultimate brings out so much in recordings . . . and the Ultimate brings out a lot more than the Blue . . . the Ultimate often gives the feeling of having elevated my system to the next level . . ."

In addition, before you changed fuses, did pianos not sound like pianos? If not, what did they sound like?

Did voices not sound like voices? If not, what did they sound like?

Sorry for the delay, Ron, but I have not been receiving emails from this thread although I have "instantly" checked.

In your first snippet, it looks like you mangled what I wrote: I did not write the the Ultimate has PRaT galore and what else follows in your quote, but that the SR Blue does! Continuing, I stand by the "much greater" for the Ultimate. Listen for yourself and see what you think. I meant what I said about elevating the system. It's like all of a sudden I had - and still have - a sense of entering another level of system. By comparison, the SR Blue's were more of a substantial quantitative improvement in some respects, while leaving me fundamentally dissatisfied in the most important (to me). Pianos sounded a "1/4-1/2" tone high, something that is quite common in revealing gear. I don't recall the Blue's voices now, except that they were a bit recessed. One of the surprises was how much more revealing and musical the Ultimate's addition made poorer recordings, although weak recordings are still weak recordings.
 
Dear highstream,

Thank you for your very well-written and understandable comparison of these fuses. I truly enjoyed reading the report.

But I have received a complaint from the Hyperbole Police. They have requested that I ask you to confirm or explain some of the statements in your post.

I am sure you are correct that the fuses sound different, but are you certain the comments in italics are correct, measured, proportional and not exaggerated? Thank you!

“. . . Audio Magic SHD Ultimate beeswax . . . substantial improvement over the SR Black . . . how much it made the music swing; it's got PRaT galore! It's also brings a very quiet background. . . which adds a sense of considerable transparency and expansiveness. . . .”

The effects of the Ultimate beeswax . . . much greater tonal/timbral accuracy - e.g., pianos sounded like pianos, voices like voices . . . Bass comes across more substantive and precise . . . Image stability is very decent. . . . bringing out so much more in recordings . . .”

“. . . The Ultimate brings out so much in recordings . . . and the Ultimate brings out a lot more than the Blue . . . the Ultimate often gives the feeling of having elevated my system to the next level . . ."

In addition, before you changed fuses, did pianos not sound like pianos? If not, what did they sound like?

Did voices not sound like voices? If not, what did they sound like?

Sorry for the delay, Ron, but I have not been receiving emails from this thread although I have "instantly" checked.

In your first snippet, it looks like you mangled what I wrote: I did not write the the Ultimate has PRaT galore and what else follows in your quote, but that the SR Blue does! Continuing, I stand by the "much greater" for the Ultimate. Listen for yourself and see what you think (if you do, search the various dealers for best pricing - or contact me). I meant what I said about elevating the system. It's like all of a sudden I had - and still have - a sense of entering another level of system. By comparison, the SR Blue's were more of a substantial quantitative improvement in some respects, while leaving me fundamentally dissatisfied in the most important (to me). Pianos sounded a "1/4-1/2" tone high, something that is quite common in revealing gear. I don't recall the Blue's voices now, except that they were a bit recessed. One of the surprises was how much more revealing and musical the Ultimate's addition made poorer recordings, although weak recordings are still weak recordings.
 
For those who play with fuses, have you found it worth putting better fuses in subs? I’m about to replace SR Blacks in a pair of ATC actives with Audio Magic Ultimate Beeswax SHD’s and also have a pair of JL Audio e-110 subs I'm about to set up. I’m wondering what others’ experience has been changing the fuses in subs, whether you’ve found it worthwhile or just a marginal improvement, if any. I expect the crossover will be at about 55 Hz. Thanks,
 
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Well I might be a fairly lonely voice of dissent here in regards to the SR Blue. Last night I replaced the stock fuse in my EAR 890 with a brand new 4A SR Blue, and I am decidedly disappointed. People have told me these are supposed to sound good right out of the box, so I don't know if I should give it time. But the SR Blue sounds distant and compressed vs the stock fuse. It lacks the air and openness of my stock fuse, it truncates decay and mutes treble shimmer, and is a tad bloated and less articulate on the bottom end. Kind of a thicker and slower sound that's less extended in both directions. So overall not a good showing. In fact, it didn't last more than one side of one record before I said "meh" and went back to the stock fuse.

Should I expect dramatic improvement here, or should I send it back now? I hardly have the desire to sit around waiting for it to improve, but could be convinced to reconsider.

EDIT: On the positive side, the SR Blue is a bit quieter than my stock fuse. But the slightly blacker background is probably related to the slight veil over everything that has been introduced.

Thanks!!
 
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Bazelio, you should PM Blue58.
He lashed up a rig to burn in the Blues 24/7.

It took 300 hrs for them to open up.

Personally I find that figure preposterous. My analog reinstall incl new psus took 80 hrs, and that was right at the limit of my endurance.
 
Well I might be a fairly lonely voice of dissent here in regards to the SR Blue. Last night I replaced the stock fuse in my EAR 890 with a brand new 4A SR Blue, and I am decidedly disappointed. People have told me these are supposed to sound good right out of the box, so I don't know if I should give it time. But the SR Blue sounds distant and compressed vs the stock fuse. It lacks the air and openness of my stock fuse, it truncates decay and mutes treble shimmer, and is a tad bloated and less articulate on the bottom end. Kind of a thicker and slower sound that's less extended in both directions. So overall not a good showing. In fact, it didn't last more than one side of one record before I said "meh" and went back to the stock fuse.

Should I expect dramatic improvement here, or should I send it back now? I hardly have the desire to sit around waiting for it to improve, but could be convinced to reconsider.

EDIT: On the positive side, the SR Blue is a bit quieter than my stock fuse. But the slightly blacker background is probably related to the slight veil over everything that has been introduced.
Thanks!!

If you check back two or three pages for my review, you'll find the voting for Blue is not unanimous. However, I wouldn't definitively judge a fuse until 400 hours have passed. It's too big an investment to rush things. For burn in, I typically run the gear it's in for two days, then let it recover overnight, then repeat that for just over two weeks. If you have a 30-day trial, it can be spaced out more.
 
If you check back two or three pages for my review, you'll find the voting for Blue is not unanimous. However, I wouldn't definitively judge a fuse until 400 hours have passed. It's too big an investment to rush things. For burn in, I typically run the gear it's in for two days, then let it recover overnight, then repeat that for just over two weeks. If you have a 30-day trial, it can be spaced out more.

Thanks. Yeah, the thread is 56 pages, and it's hard to know where the truly useful tidbits lie within it. I think I'll rig a lamp cord to the fuse and connect it to a low wattage bulb that I can just leave on for a week or two. Though, as I said, this thing is going to need to dramatically improve in order to be a keeper. You are right, though - I shouldn't give up after 20 minutes of music!
 
So are the beeswax fuses the subject of a broader consensus as to improved sound quality?
 
Well I might be a fairly lonely voice of dissent here in regards to the SR Blue. Last night I replaced the stock fuse in my EAR 890 with a brand new 4A SR Blue, and I am decidedly disappointed. People have told me these are supposed to sound good right out of the box, so I don't know if I should give it time. But the SR Blue sounds distant and compressed vs the stock fuse. It lacks the air and openness of my stock fuse, it truncates decay and mutes treble shimmer, and is a tad bloated and less articulate on the bottom end. Kind of a thicker and slower sound that's less extended in both directions. So overall not a good showing. In fact, it didn't last more than one side of one record before I said "meh" and went back to the stock fuse.

Should I expect dramatic improvement here, or should I send it back now? I hardly have the desire to sit around waiting for it to improve, but could be convinced to reconsider.

EDIT: On the positive side, the SR Blue is a bit quieter than my stock fuse. But the slightly blacker background is probably related to the slight veil over everything that has been introduced.

Thanks!!

Have you tried reversing the direction of the fuse?
 
Ron, you didn’t know?
 

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