Fuse upgrades? -- 6.3 amp 250v 5X20mm fast blow fuses


I occasional blow a one of these 4 fuses in my McCormack DNA .05 and use cheap fuse replacements costing maybe $.50 a piece.  Can anyone recommend upgrades fuses that might enhance the performance of the amp, but not costing in the SR price range.  Say $1-$5 a piece?   Thanks for any insights.    
whitestix
I doubt very much that a more expensive fuse will alleviate the fuse blowing trouble you are having! 
https://www.parts-express.com/littelfuse-63a-gma-type-5-x-20mm-fast-blow-fuse-5-pcs--071-834
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Cooper-bussmann (USA), LittleFuse(USA), Schurter(Germany) ....and the the favorite of the Japanese audio business for over 50 years, SOC of Japan.

look for long lag fuses from any of those companies, and you'll be part way to the higher end audio grade fuses for a few bucks a pop.

Make sure you replace with the same type (fast low, normal blow, and lag types) as the manufacturer recommends.
That’s fine if you’re a Japanese businessman. But the favorites of real Japanese audiophiles are Isoclean, Furutech, HiFi Tuning, SR and Audio Magic. They eat the Bussman and Littelfuse for breakfast. 🍳 🥞 ☕️
Thanks for the insights, gents, much appreciated.  As you have noted, fuses blow for a reason, and I think in my case it has been due to poor connections with my interconnect cables and me fiddling with gear on rack.  I plead guilty!   I ordered some new bussman fuses as replacements and will ensure more firm connections with my cables to the gear.  Thanks again. 
Geoff,
Thanks for chiming in.  I will admit that Steve McCormack is a devotee of SR fuses and he knows audio gear. 
@whitestix SR hasn’t sold 30,000 fuses for no reason.
30k fuses, eh?

You’re makin’ me think I should go back and finally finish the fuse tech I was working on (tinkering with, off and on) for nearly a decade, and finally bring it to market.
Before we have a zealot coming in and reducing this thread to a troll fight, I will say that fuses are a way to tune your sound.  There's no right answer and I have actually used different fuses in different situations to "adjust" the sound.
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Such as, Furutech are probably the most neutral high resolution fuse.  However, too many Furutech in one device can make things too warm/slow.  If you have 4 fuses in the DNA, you probably have a single "Main A/C" fuse.  I would do the 4 fuses all Furutech and then keep the stock fuse for the Main A/C or look at faster alternatives.
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Hi-Fi Tuning Supreme is a silver/gold mixture and it is a much faster sound with faster attack and more detail.  However, it can easily push a system over the line into the "too fast/bright/harsh" area. 

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Isoclean or Hi-Fi Tuning Supreme "Cu" (copper).  These are gold-plated copper and can be used to make a system warmer sounding.
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There are others you can play with, but I haven't tested any of the other new offerings.
Another note.  I haven't tested the Synergistic BLACK/BLUE fuses. The older SR20 fuse is very clean and fast, but it lacks the high frequency response (so it sounds a little like a Class D amp would).
The Synergistic "RED" fuses is about the least offensive fuse.  It will sound okay in any system, but it is slow and not very detailed.  The Isoclean actually gave more detail and resolution, even though it was still a warm sound.
Fuses have no bearing on sound quality unless they are directly between the output stage of the power amps and speakers. Remember, it is the secondary of the amplifier’s power transformer that does all the heavy lifting (typically 5:1 current ratio relative to the primary winding), augmented by the filter capacitors on more demanding load peaks).

The OP’s problem is probably exacerbated by the design spec for his amplifier fuse leaning towards the conservative side, more judiciously protecting the amplifier. I suspect tolerance of the fuse in that case might be a factor also, making the likelihood of blowing a fuse even greater. If it were my gear, I’d take some current draw measurements to get an idea of how close to the threshold the amplifier is running. Consulting with the manufacturer would be prudent, in case they have come across other such cases and deemed that a change in fuse rating is warranted to mitigate nuisance blowing of fuses.
The problem is usually that the fuses (any fuse) cannot be easily made to complete their required job successfully and at the same time handle large transient functions. No one has done it so far, not any ’audiophile’ fuse, either, unless they skirt the edge of proper legal descriptive and actual function of a fuse.

To add, they are highly non-linear, at best....quite large non linear odd order distortions, when under complex dynamic loading, which is what is inside an amplifier.

Tests done with thin wall 99.99% copper tubing as fuse substitutes (found at the given local hobby supply shops), illustrates quite dramatically...just how bad fuses sound. It almost sounds like a double or triple equipment upgrade. It is not subtle. I exaggerate, but not by much. Depends on how the given listener...listens, it depends on what they listen for.

Doing this experiment is not recommended, as one would be incredibly tempted to leave said test devices in place. Unstoppably so. (one would be begging for just one more minute of that incredible sound....!) Unhearing this is pretty well impossible, and will haunt one forever afterward. Do not do this unless you wish to be ruined.

But all of that aside, audiophile fuses sound better than any stock fuse, including Bussman and Littelfuse. Do all audiophile fuses sound alike? Heavens, no! But they’ve come a long way, baby! That’s why audiophile fuses are more popular than ever. You know, with around 30-40,000 in the last few years alone. Hel-loo! Go, ahead, do yourself a favor. Don’t be a cube, rube. Hop on board the fuse train. 🚂 Toot! Toot!

Can’t do this, can’t do that, too complex? Whoa, what’s with all the negativity? Don’t say can’t. Be like the Little Train that could. 🚂 Toot! Toot!
sleepwalker65"Fuses have no bearing on sound quality unless they are directly between the output stage of the power amps and speakers."

Yes we can understand that this is your faith, belief, and unshakeable conviction and that your belief is based on what you feel to be reality based on certain information available to you but that is limited in scope, authority, and completeness but what I recommend you undertake is exploring the real world that exists outside of your little computer before pronouncing hear your ill-considered conclusions that are derived from source(s) you don't even bother to reference, identify, or substantiate. 
@clearthink I am very well-informed, having an engineering background and work in the broadcast media industry. I know what limits the DC power supply places on sound quality, and fully understand the ramifications of placing a weak link in the chain of power delivery. Your comments betray a lack of understanding of how power supplies function.

You can choose to believe in unquantifiable properties, while I believe in the works of the esteemed scientists who authoritatively laid the groundwork of all modern electrotechnology: Georg Ohm, Heinrich Hertz, James Watt, Joseph Henry, Alessandro Volta, André-Marie Ampère, Michael FaradayCharles-Augustine de Coulomb, Nikola Tesla, Gustov Kirchoff, Thomas Edison, John Bardeen, Walter Brattain, William Shockley and many others. Believe what you want to, but please refrain from disparaging  others. 
auxinput and sleepwalker,
Much obliged for your thinking on this issue.  I tried a couple of SR Black fuses in a former amp and preamp and perceived no difference in sound.  I have some Hifi Tuning fuses in other gear and never think much about them, but I might get a set for my McCormack.  It seems for every "fusehead" around, they are just as many EE's and other tech's who scoff at the idea of fuses making a meaningful difference in sound.  This controversy will never be settled, and while I won't pop of the SR fuses, less expensive one like Hifi Tuning are a fair gamble.  Again, Steve McCormack is a believer in SR fuses yet the fellow that created my preamp thinks it is pure folly.  I am somewhere in the middle.   Thanks again your all your posts.  
auxinput and sleepwalker,
Much obliged for your thinking on this issue.  I tried a couple of SR Black fuses in a former amp and preamp and perceived no difference in sound.  I have some Hifi Tuning fuses in other gear and never think much about them, but I might get a set for my McCormack.  It seems for every "fusehead" around, they are just as many EE's and other tech's who scoff at the idea of fuses making a meaningful difference in sound.  This controversy will never be settled, and while I won't pop of the SR fuses, less expensive one like Hifi Tuning are a fair gamble.  Again, Steve McCormack is a believer in SR fuses yet the fellow that created my preamp thinks it is pure folly.  I am somewhere in the middle.   Thanks again your all your posts.  
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sleepwalker65
You can choose to believe in unquantifiable properties, while I believe in the works of the esteemed scientists who authoritatively laid the groundwork of all modern electrotechnology: Georg Ohm, Heinrich Hertz, James Watt, Joseph Henry, Alessandro Volta, André-Marie Ampère, Michael Faraday, Charles-Augustine de Coulomb, Nikola Tesla, Gustov Kirchoff, Thomas Edison, John Bardeen, Walter Brattain, William Shockley and many others. Believe what you want to, but please refrain from disparaging others.

Best Name Dropper of the Week goes to....sleepwalker!

Joke. Who invented the steam engine? Watt. Who invented the steam engine? Watt. Who....
Couple of additional thoughts.  You may not hear a difference with fuses.  Your equipment/speakers may not be high enough resolution to hear the differences.  On very warm equipment, just putting in one Hi-Fi Tuning fuse may not may any significant amount of difference (especially if there are 3 other fuses that are working in conjunction).  If you have 4 internal fuses on the DNA, I would suggest upgrading all 4 of them to get an "idea" of what a specific fuse is doing.  I suspect they are all post-transformer or post-regulator fuses (2 for each channel).
@auxinput I agree, any fuse that comes after the power supply filter capacitor(s) has potential to affect current delivery and hence sound quality. For that reason, I prefer fusing only on the power transformer primary side, where it should have zero impact if not sized too conservatively. Also, I prefer fast acting fuses on everything except the power amps, due to the nature of high and very brief instantaneous current demands. As usual, in keeping with safe operation, as long as the manufacturer recommends a slow-blow fuse, that is the only situation when I would use one. 
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Gents, thanks again for chiming in on this now-contentious post... could on GK to throw voodoo dust over sound electrical theory.  I am taking auxinput's advice and replace all four rail fuses on my DNA .05 with these ceramic fuses from Bussman, costing $5.00 each. Worth a try.

 

Bussmann 

Miniature Fuses, GDA Series 

Item# GDA-6.300A - FUSE, 6.3A, 250V, F, 5X20mm, CERAMIC 

GDA Series Information
  • 5 x 20 Millimeters
  • 0.05~6.3 Amps
  • 250VAC
  • Fast Acting
  • UL Approvals
The Bussmann GDA Series are a group of low voltage, general purpose miniature fuses. These fuses are designed for use in appliances and consumer electronic equipment.

  • High Breaking Capacity
  • Optional Axial Leads
  • Ceramic Tube
  • Nickel-Plated Brass Endcaps

Gents, thanks again for chiming in on this now-contentious post... could on GK to throw voodoo dust over sound electrical theory.  I am taking auxinput's advice and replace all four rail fuses on my DNA .05 with these ceramic fuses from Bussman, costing $5.00 each. Worth a try.

 

Bussmann 

Miniature Fuses, GDA Series 

Item# GDA-6.300A - FUSE, 6.3A, 250V, F, 5X20mm, CERAMIC 

GDA Series Information
  • 5 x 20 Millimeters
  • 0.05~6.3 Amps
  • 250VAC
  • Fast Acting
  • UL Approvals
The Bussmann GDA Series are a group of low voltage, general purpose miniature fuses. These fuses are designed for use in appliances and consumer electronic equipment.

  • High Breaking Capacity
  • Optional Axial Leads
  • Ceramic Tube
  • Nickel-Plated Brass Endcaps

Sorry for the double posts, I am getting error messages. 
"Nickel-Plated Brass Endcaps"

that part you do NOT want.

You want silver plated brass.

One can hear the nickel, in a good system. The McCormack is one of those ’good systems’.

When you get the error message, that exact one, you can just reload the page and the post generally appears.

If not, or not wanting to risk losing the post... just kill the extra post afterward. It’s a permanent edit function available for the given poster.

eg, I can still remove all trace of all my posts, on this forum, at least the bits that have not been quoted. One at a time.

As for sound electrical theory, Geoff’s not really throwing fairy dust over it, it is just that measurements have little to do with how the ear or the amplifier works, beyond a vestigial connection.

Somewhere around 99.99 % of the people here who talk about electrical theory and measurement being king do not design and sell amplifiers and have pretty well zero actual lore and knowledge in these areas other than dogmatic text based references. It’s a very poor and weak position. Like debating football or hockey. Armchair stuff. They're not a  player and they're not in the field.
Yes, audiogon is suffering from a lot of web site errors and instability this weekend.  I usually "copy" my entire post before hitting "submit" just in case the site jinks.
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Yeah, I agree that the cheap fuses with nickel plated end caps are not that great.  I just did a comparison of cheap ceramic fuses between Bussman and Littlefuse.  In this case, the Littlefuse brand won out.  The Bussman had somewhat of a warmer/slower sonic signature.  The Littlefuse did not have this warm signature and was clearer/cleaner.  That being said, it was a stop-gap and I already have a couple of Hi-Fi Tuning Supreme fuses on order to replace these, lol.
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However, I don't necessary agree with teo_audio that you want silver-plated brass.  1 - silver plated can be useful, but in some situations it is just too fast/bright/harsh.  2 - Brass has never had good results whenever I have tested with it.  Brass usually pushed too hard on the signal and can come across as too strong/harsh.
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Furutech have wire/end-caps are pure copper that is Rhodium plated.  Hi-Fi Tuning Supreme is a silver/gold mix for the wire/end-caps.  Both are excellent, but have different results.
The better fuses from the mentioned companies have beryllium copper end cap available, IIRC. Brass is the second down on the preferred ’cheapies’ list. so,silver plated beryllium copper or what is normally available: tin plated beryllium copper end caps. IIRC, of course.

Digikey probably has the best search engine around for figuring all this out, re targeting the desired items...
Honestly, I would rather get tin-plated beryllium copper (which is usually mostly copper with 2-5% bronze) then the most expensive silver-plated brass.  The tin plated copper is not that bad and it is definitely more neutral than silver plated or gold plated.
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@clearthink wrote:
You have the active fantasy life of a small child... from your mountaintop of ignorance, confusion and disorientation.

@clearthink, Would you care to explain your assessment?  
This is going reasonably well, you know, considering it’s a fuse thread.

If you think UL losing is a big audiophile issue for fuses just ask the 70 or 80 thousand audiophiles who opted for non UL listed aftermarket fuses. And if you insist on something fast acting try some fast actin Tinactin. We want tuna that tastes good, not tuna with good taste. 🐬
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Why on Earth would you put fuses anywhere except on the primary of the transformer? The only reason I can imagine is to idiot-proof things because you're customers require idiot-proofing.
Kosst, 
In my Platinum upgrade of the McCormack DNA .05, Steve has four FB rail fuses, two on the main circuit board, and a fuse ahead of the transformer.  I don't know his logic for using so many fuses, and I have blown a few of the rail fuses with poor IC connections, but it is the finest amp I have ever heard.  I think he used the fuses perhaps to idiot-proof them, which I will admit to being one.  Cheers, Mark