How & why are fuses directional?!

Removing the fuse to turn it round involves unplugging the plug from the mains socket. In which case, there will be a small amount of oxidation removed from the plug contacts, socket contacts, fuse holder and fuse end plates because each of these clips is quite strong. If you repeated this process twice so the fuse was back in place the same way round, do you also find a sonic improvement because of the contact cleaning? Please also don’t touch the fuse end plates with sticky fingers as this will leave an oily film so negating the experiment.


@Peder please don’t stop sharing your experience and knowledge. Ignore people who prefer to win an argument than to actually learn something.

I did a comparison of a custom made SPDIF cable BNC to coaxial using a high gauge wire terminated by Gothic Audio with a Wireworld Micro Eclipse AES cable that costs hundreds of pounds more. Till today I have not been able to discern an audible difference between the cables. Now does that mean there is no audible difference? not necessarily. In my application I am not able to pick up on it but somebody else may experience a difference in a different setup.

I don’t live life with pre determinations about anything. Every day is a school day and I don’t believe measurements prove everything.

It’s now common knowledge that a silver conductor cable built exactly the same as a copper one will sound different. It wasn’t so long ago that this was considered to be a ridiculous assessment.


Didn’t imply it was yours it looks like a publication picture.
Seems like they don’t know much about what they are selling.
It’s amazing what trivial seeming items are faked but it must be worth it to them. :scream: :-1:t2:

Hi :slightly_smiling_face:

Everything you describe is very relevant.
Myself I take into account all such aspects in evaluations.
Pulls the plug in/out 6 times,.also the fuse in the fuse holder etc…

Clean the fuse ends and other parts with isopropyl alcohol,and use “rubber gloves” when I handle the fuse etc.
All to ensure a good test methodology.
Good that you brought this up because it is important to obtain a safe result.


Cam/timing belts have been faked to appear to be made by Gates (one of the best manufacturers).

Bosch fuel pumps have been faked too.

Both of these can leave the car owner with a hefty bill due to engine damage.

All Gates belts now come in hologrammed boxes to combat fakes.


Just go with the flow,
Not just your orientation

I seem to remember from the enormous cables and switches thread that we had on this forum that you claimed to find an audible difference between using different ports on your digital switch.

Or did I imagine that?

That seems to me to be at or beyond the outer limits of the possible.

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Can you say in a few words what the technique of tune dem consists of?

Strong words for a bloke with a full loom of Nordost cables! :nerd_face:

Hey, what a great neologism.

That’s me, that is.

Are you talking about the plug fuse or the equipment fuse?

I hardly ever listen to music with voices or singing in it so I don’t bother to test for that.

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The real question is, are records directional?


Only when you are listening to Black Sabbath albums :rofl:

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I’ve tried flipping them over and the music did sound different……


I have been thinking about all the records I love and what if the fuses in the guitar amps and recording consules were the wrong way round.

Wouldn’t the music have sounded so much better if they had them the right way round.


Well there’s a 50/50 chance of them being the right way around, perhaps that explains why some recordings sound better than others. Seriously though, I worked in the pro recording industry most of my working life, never are things such as fuses, mains or ethernet cables, directionality etc etc ever considered or even discussed. I think the reason why they only feature in the domestic market lunatic fringe is fairly obvious… $$$$$$$$


@Peder has done so previously - which is from where I took my understanding, but in this thread he has expanded to say it is not so simple and you need to learn it from someone who understands and knows how to do it, so maybe it doesn’t lend itself to simple explanation without being misleading?

Kind of, the equipment protection fuses that many fit to larger devices with inductive loads including Naim who fit to many of their devices, which are said to exhibit some subtle directionality traits, are slow blow fuses. That is they let an initial surge of current through exceeding the quiescent rating of the fuse. This is to allow current surges due to initially powering a relatively large transformer to not blow the fuse, but still adequately protect the devices. This is why you may see filament lights dim very briefly when you start a large motor or transformer device in your house. The current trips on your consumer box are also graded for different current surges and quiescent current.
Generally equipment fuses are graded as very fast (FF), fast(F), medium(M), slow(T) or very slow(TT), and are categorised into low, medium or high current breaking. Naim typically use slow or very slow acting I believe. The markings are typically stamped on the cylinder end. The correct term for slow blow is Timed or T fuse.

If you look carefully at many Naim T fuses, you will see a spring inside, and this pulls the elements apart once the wire has sufficiently heated and breaks open. The surge takes time to heat the wire… so if the surge is quick as it should be the spring has not enough energy to break the heated wire before it cools again. I suspect it is this mechanical aspects that vibrate differently in the fuse holder depending on which way they are inserted, and it is this that may super subtly change the mains power quality … but it does feel it’s going to be minuscule.

Fuses inserted in a UK plug are there to protect primarily the cable flex and its current capacity to the appliance … this should have very little inductive property and so should blow mediumly quickly. They are a relatively crude device.

Whatever the fuse type, it’s always important to fit the specified rating. Manufacturers who use equipment fuses will typically state the required replacement fuse type, and often provide a spare.


Power blocks and conditioners have a similar trait, things need to be plugged in in a certain order. Sometimes there is an order to things.

I’ve never tried it myself but I wouldn’t discount it as it will all depend on how the switch is wired / setup and the quality of isolation between each socket in terms of electrical noise. Who knows… sometimes it’s best to have an open mind otherwise you would never experiment and find out new things!

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