Higher amperage fuse for sound quality

I apologize if this question is either (1) ridiculously stupid or (2) already been beaten to death. And I'm definitely not looking to re-litigate whether aftermarket fuses are anything other than b.s.

I've read that people sometimes choose higher amperage fuses. This is because aftermarket fuses are supposedly built to tighter specs and therefore prone to blowing. Supposedly SR is noted for this.

Recently I was looking into some SR fuses and the dealer told me that higher amperage was also better for sonics. I'd never heard that before.


So last night I was looking through my stuff and discovered an unused 3.15a fuse. (I used HiFi Tuning throughout.) I decided to try it in my transport which takes a 1.6a. Everything is plugged into a Shunyata and there were no signs of t-storms so I figured I was safe for an hour or so.

It made the single biggest difference of any "tweak" I've tried. For one, the bass went significantly much deeper, became more authoritative, more controlled, more precise. The treble lost whatever edge it had and became golden and bell-like. Aside from those things, the music generally became more musical, which is difficult to explain. The music "might" have lost a tad of nuance and subtlety but I'm not sure. It's a small exaggeration to say that it sounded like a different amp. 

Being risk averse, I switched the fuse back, but I'm still so surprised. Has anyone had a similar experience? 


I'd say it was time for a fuse holder clean up and new fuse in the right direction. I'd be looking at a PC too if a fuse made that kind of difference. Some manufactures equipment react differently than others to fuses and power cables. It usually points to maintenance and the quality of the power supply. I'd say your change was due to poor contact and an old fuse.

Short answer is no I haven’t experienced anything like that. If you want to confirm your findings, have someone switched the fuse ten times and see if you can tell which fuse is in at any given time. See if you can guess correctly at least 50% of the time.  In terms of leaving that fuse in without risk, ask yourself this question: have you ever had to replace a blown fuse before in one of your devices? I haven’t in forty years. In my Melco server, the manufacturer is so certain they used the best possible fuse that they soldered it in so as to discourage replacement. When I swapped SR Orange in my amps, I only got a little bit more resolution but nothing to write home about. But I only jumped a little bit up on the amperage though. Good luck. 

I have experienced this in source equipment.  If the stock fuse is 500 mA or 1A, I will often bump this up to 2A, but that is as far as I will go.  Fuses in amplifiers usually don’t see any benefit from increase since they are often already 6+ amps.

I read here on AG that a cold start with a regular fuse can take up to an hour to recover from the a hard cold start. That is the main reason boutiques sound better and over time stay sounding better. That little wire isn't moving in a fuse filled with a dampening and heat sink material, it never gets hot like a standard fuse on startup..

Cold start a 3.5amp stock fuse 30 times and look at the wire inside. It use to amaze me when I'd change the fuses in my old speakers. Tightening driver screws and changing fuses was like getting new speakers. Amps; any fuse with a dampened wire, barrel and goo will work for me. -------> please not <-------- way. It matters. I don't know about SR but most the fuses I use sound different one way vs the other. ACME with a crinkle coat is a good fuse.

Pingstonsmile, thanks, I hadn't thought of that. The fuses are both just a few months old and the fuse socket is from a new component, but maybe I should hit it with some Deoxit. 

For a low-draw piece like a transport, it seems like it shouldn't be too dangerous to run the higher fuse. Makes me a little queasy though. 

Only do this if your ok with taking out the actual job of a fuse, and are ok with the risks. I.e. to protect your home from burning down. 

But is it likely that a transport would suddenly draw such a surge of energy? 

Huh, could it be a defective fuse? The Monday morning fuse, not quite up to standards?

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The equipment fuse is for the equipment, not fire protection. The house breaker is for fire protection. The only equipment in my house with a fuse is the garbage disposal and my shark vacuum cleaner. The stereo does but the TV or hardly anything I know of does have a breaker or a fuse. 

If you hear the difference using a piece of solid stock silver or copper from startup, the chances are you might hear a difference with a boutique fuse change. It's the recovery time after startup that I notice. Some fuses never have to recover and sound GREAT (a boutique). A standard Bussman is just good enough to keep the AC flowing. There is a reason WHY some fuses sound different than others. It's not Hocus Pocus. There are some interesting threads about fuses here. Bass is the first place to suffer. Supply and demand..

Fuses are there by design to protect your gear. There are many safer and way more effective ways to muck with the sound. Use a good quality fuse with the proper specs as per manufacturer and move on. That is the smart and cost effective thing to do.

Thanks for the comments. I am most definitely not looking for an excuse to use the higher amperage fuse. I am just wondering why it sounds this way. Both fuses are HFT, both clean and shiny. I bought the 3.15 a few months ago while the smaller fuse might be 2-3 years old, if that makes a difference. Honestly I find it hard to believe that this amount increase in amperage (or any amount) could make such a difference, but maybe I'm wrong? Maybe the "improvements" that I am hearing are actually the result of the machine running too hot? 



It’s not the increase in the amperage of the fuse. It most likely was just the fuse change. Pulling and replacing the fuse cleaned the contacts. You can prove that by reinstalling the old fuse. If the sound is good it was the contacts. If it returns to the old sound the fuse wire is NOT recovering after a hard start. A new fuse might, and older fuse with a metal fatigued thermal wire might not..

You can figure out why easy enough.. It’s not about resistance when everything is perfect, it’s when you keep pushing that cheap little wire beyond 20 cold starts.. That is where boutique fuses seem to shine and stockers don’t.

"Don’t worry be happy"🎶

Keeper Of the Seeds. aka "KOS"

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You've never heard that before because it's patently ridiculous. As others have said, it's not good to put in a higher amp fuse than what the manufacturer specifies. Would you put in a higher amp circuit breaker for your oven so it could reach a higher temperature despite having the same wiring and insulation in the appliance?

Yes, but he is asking WHY it sounds better not how to cook a pizza faster. A little different I think. One is for fire protection (the stove).  The other is for equipment protection. There are No fuses on my TV. I have a reset button on my table saw and the garbage disposal. That's so I don't burn the motor up if something gets stuck. There is not much of a chance of a fire though. Why is there a fuse in them to begin with? Not required by law is it? Equipment protection is for stereo equipment. Maybe something left over from using valves..

Rolling ON with a Variac helps a lot with my old tube amps. They never pop fuses. You flip a switch they will. They sound bad when you start them like that too IF you don't blow a fuse first. Citations and Marantz both sound better with a soft start..

Try pulling the fuse out sticking solid wire stock in its place, Bingo same sound ? Then try different copper, steel, silver, same sound ? Make sure the right spec fuse is then installed to do all that a fuse is designed to do and that is to protect from an overload !! The rest is just plain BS.

I can understand that an improvement may be made. But isn’t it akin to running nitrous in your car? Yes, that car will run much faster with the nitrous. You may only get it to run for few thousand miles before a rebuild, but you can have fun until then. But you will have to pay a good sum for the fun you had.

If you have the money to spend, then fine. It's your toy. But warranty is  void because it is abuse. Unfortunately some abuse and damage their equipment and then sell it on A'gon to others as gently used 

The fuse is there to protect your equipment and its amperage is determined by the manufacturer from his knowledge of the equipment.

Don't mess with it.

There are some people here who in the past have advocated replacing the fuse with a solid metal bar.  I hope we all know not to go there.

Don't mess with it lol, because it's in the manual it must be safe and correct is full of crap( wow rule follower,  and don't eat pizza it's bad for you)Its usually under valued to be extra safe and cautious. If you are getting better sound try a bit higher fuse, but a double might be pushing it. I have a old sweet sounding class A ,Jeff Rowland amp, but the 5amp fuses would blow when I cranked it up very loud. So I called , talked to Jeff Rowland personally and he said then why not put a 6 to  8 amp fuse in it, it will handle it no.problem. I run a 7amp right now 6 months no blow and sounds wonderful. So even if it came with 5 amp most should handle a bit more no problem, but it is built like a tabk


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Amen to the common sense practical thinkers here.

More are neede

Amen to the amen. People post such garbage here.

Pingstonsmile, in fact I did swap the fuses back and forth 2-3 times to confirm, and the results were the same. You might be right about the smaller fuse being compromised, but as for cold starts, I leave the transport powered on continuously, so it hasn't been exposed to daily cold starts. (Although I don't exactly remember the history of this fuse. It might be 2-3 years old and might have been used in a tube amp that did get turned on and off. However it looks brand new, there is no discoloration, etc.)

Maybe I should go to the hardware store today and get two fuses and see if they show similar results. I suppose that would indicate if my HFT fuse is weakened. I hope that's the case. I'm rooting for a simple explanation that can be easily rectified. I don't wish to use a wrong-size fuse. 

I would not be screwing around with higher amperage fuses. The fuse present in the devise was designed to be sacrificial and to blow at a certain predetermined parameter, to protect the electrical circuit(s) upstream. Besides, a fuse should not make one iota of difference when it comes to what you are hearing. 

This got me to thinking (always dangerous) about what is the manufacturing tolerance of any given fuse.  Fuses are not perfect, so Googling I go. Turns out that a typical fuse is 90-110% of its published rating.

Does anyone know if SR or HFT or whatever boutique fuse are held to a tighter tolerance?

Wonder why it has been reported here many times over that SR fuses blow a lot and they have a free replacement policy of some sort.  And my understanding is they typically suggest to increase the fuse rating.

The mind wanders.



Rambling speculation (only) on my part.

I would think that the amp designer voices an amplifier or preamplifier to sound a certain way he/she considers ideal.  If he/she wanted the amp/pre to sound as it does with a boutique fuse or different amperage fuse he would have voiced the amp/pre to sound that way without needing to use a boutique or different amperage fuse.

Conversely, if he had originally designed the amp/pre using a boutique or different amperage fuse he probably would have voiced the unit to sound identical to how it would have sounded with the non boutique fuses.

In other words, he had a voicing he was aiming for and that voicing is what he thought was ideal.

I agree with Mapman......  the fuse is that spec to protect the device.   I always replace with exact fuse.   Asking for trouble.

@jetter    Sorry.  You're completely wrong.  All the amateur non-engineers here know far more about amplifier design than all the amplifier designers.


There you go OP. I'd get a new fuse and see if the old one had an issue. I trust my ears. But I still like to know why. That little wire can be a PITA. Considering everything to that point is probably 14 gage or better. They do make slow blow fuses for a reason. They get hot on startup. It wasn't uncommon for a manufacture to UP the amperage on a fuse. Cary sure did it. A few times. The only thing it stopped was a trip to the hardware store every other week to once a year.
A boutique with good dampening and a way to get rid of the heat quick, 5 years and counting on some of mine. Tube amps are tougher on fuses, no doubt. I Variac up my old amps. It's easier on everything, especially tubes and transformers.

Voicing with a fuse  ???? utter garbage. IT's a FUSE and nothing more ! Think of it as a protected power bar....Bingo. If that's to hard to grasp there's much bigger problems out there. 


The purpose of a fuse is to protect the equipment so it can't draw too much current. For whatever reason, be it too loud or a component failure. I certainly wouldn't exceeding specifications.

A slow-blow fuse could be an option in certain circumstances.

Pingstonsmile, even better, I located the stock fuse. Looks to be ceramic. Anyway, with this fuse, the sound was closer to the smaller HFT fuse than the larger. So the mystery remains. Why does the system sound different when just one upstream component is running a fuse roughly one amp higher than normal. Does a simple machine like a transport (not even a CDP, but a transport) pull such large current that it's throttled by a 1.6a fuse? What would happen if I installed a 10a fuse? Would it blow out the windows?

So far only 'auxinput' has stated that he's seen similar results. No one else seems to have noticed such a phenomena as this. I'm really quite perplexed.  

Fuses don't 'throttle' anything. Current passes through them unhindered, unless it exceeds too high of a level, and which point the the fuse fails. It is first and foremost a safety device.

Why fuses  those who have no idea.

The National Fire Protection Association (NFPA) is a nonprofit organization devoted to eliminating death, injury, property and economic loss due to fire, electrical and related hazards. The Occupational Safety and Health Administration (OSHA) and the NFPA have written many standards and regulations that build on one another. In the case of NFPA 70E: Standard for Electrical Safety in the Workplace, the OSHA regulations and NFPA standards work so well together it’s been said that OSHA provides the “shall” while NFPA provides the “how



Are you sure it‘s the higher rating or might you actually have changed the direction of the fuse accidentslly. Fuse directionality is the result of the wire drawing process and on good systems quite audible