Hi-Fi Fuses - SNAKE OIL? - or something in it?


There's a lot of chatter about the benefits of those high prices gold plated fuses with silver conductor etc. etc. all over the web and the consensus ranges from FANTASTIC!!! to much more subtle observations.

It makes sense to me, epseically in light of spending lots of $$$ on good power cables, that having a skinny piece of aluminum conductor in a glass tube (i.e. a cheap fuse), in the power loop would be detrimental to the performance of the components.

I decided to revamp my DIY power supply I'd built for the Cambridge Audio 640p phono stage and DACmagic in order to test this out - and since it's a DIY project there is no UL Certification to void.

First, I bypassed the fuse link completely to confirm there would be an improvement and give me the best benchmark to compare against - YEP - BIG DIFFERENCE - much more this, that and the other :-)

So then I started looking for hi-fi fuses - WOW!!! - talk about pricey.

Two fuses for the power supply was going to cost $120+ AND I thought I'd probably have to buy a better quality fuse block to make the most of those fuses.

Then a moment of enlightenment - most power supplies and conditioners are protected by pushbutton breakers and not fuses.

I found breakers of the required current rating and installed them into the power supply. I imediately noticed that there was no deteriation in fidelity when compared to the same unit with the fuse link bypassed - GREAT!.

On reflection, the fuses I had in place were rated at 3 amps - so they use a pretty thin fuse wire in them. If I had used a fuse of a higher rating, i.e. it uses a thicker conductor, then I believe that there would be less of a difference between the fused and bypassed implementations

SO - do the expensive fuses work?

Well the empirical evidence out there would suggest they do
- I do know the cheap fuses are not good!

I know bypassing them does improve the sound - a lot in my case
- BUT THAT'S NOT SAFE FOR ONGOING USE

I know breakers work as good as bypassing the fuse
- BUT MESSING WITH A POWER SUPPLY VOIDS UL CERTIFICATION - NOT GOOD!
- FYI a couple of licensed technicians I know WILL NOT change the design of a power supply at all.

I believe the amount of benefit is related to the fuse rating
- but don't go replacing 3 amp fuses with a 20 amp fuse - that's not safe either.

Whilst looking for fuses I discovered AMR Gold fuses priced at $20/fuse.

Now that's definately more affordable than most others at 3-4 times their price.

One supplier I know of in the US is Avatar Aacoustics

If you have had experience with quality fuses please share - especially if they are "modestly priced" i.e. $20-$30 per fuse. And please provide a source :-)

Also, can anypne confirm that Slow blow fuses are better than regular?

And Remember - IF YOU AIN'T LICENCED - GET A TECHNICIAN!

Many Thanks
williewonka
Lacee: Thanks for the continuing discussion. The 7T back panel has no room for such a power cable change as "like a computer." I could drill out the opening where the stock power cord enters, but enlarge it to what size? One with a 20 amp capacity? or 30?...therefore the question. The power amplifiers are somewhat compact & also have no room based on layout. They have a compact inner structure with horizonatal & vertical aspects to their assembly. I could put new electrolytics in there, but the cost of them is huge.
Something like $300.00 each from what a quick web search indicated, and I'm not in a position of spend $2400.00 on the eight capacitors. If you would like, I sure there are photos of the 7T & 16 on the internet...you might get a better idea of my point of view.

WRT, could any improvements be made? I suppose so, but to me my first watt or first few watts are very pleasing to me.

As I mentioned before, at what are normal(for me) listening levels, power consumption is very low, total power consumption in the order of 150 watts or less and a voltage across 8 ohms is usually less than 2 volts.

Additionally, there is no possibility that I could ever experiment say, switching between SETs (would need 4)because the current setup is also biamplified. One would need an extensive, expensive switching setup for a task like that. One could never otherwise accurately AB test. While I hear people rave about SET apms I have not experienced one yet.

I suspect the experience might not make it to my bucket list.

But for me the question still if the monumental cost which you say you have expended would be beneficial to me.

That is way out of my price range. Thanks for your input.

BTW, years ago I did hear what was probably the "best" speaker of its day which were KLH 9s. Right where I worked, 2 pairs not 1 pair. They were pretty impressive. Then there were the Dayton Wright gas filled electrostatics which were also impressive. Neither would be suitable for SET use as I understand. These were in a shop (retail) setting, not in a well plotted out room.

Thanks for the response Gvasale,as I mentioned,some things are easier to mod than others, and what we have to accept is never the ultimate.
This could be gear related room related, power related and most importantly cash related.
We do what we do and "irregardless" or what some may think, we do reap the rewards of going the extra mile.

Those who never venture into these areas will never know how good they can make their systems sound, but then of course to their ears,what they have is the best, and everything not purchased at goodwill is a waste of money.

I have old Acoustat X electrostatic full range speakers with their matching output transformerless tube servo amps.
The speakers are directly wired to the amps, no need for speaker wires.

The amps are each powered on separate 20 amp dedicated lines from the panel on 10 guage romex and terminated in Furutech 15 amp rhodium f48 ends into matching Furutech rhodium IEC in the amps.The RCA in the amps were modded to Furutech top level inputs and the connectors of the interconnects are all CF 102R.The fuses are AMR or HiFi tuning Supremes-the less costly mods I've made.

They are placed properly in my room which is a dedicated listening room 30 x 22x8 and I have ASC room tuning devices.

I can very easily hear differences in fuses,and despite my supefluous language and lack of spelling skills,I have somehow managed to get a very realistic sound.

But it took time and effort and a few dollars to get there.

Now I can't measure the difference in sound after the upgrades,but I can hear it.
Nowhere near the sound that I had before I did the upgrades.
The fuses are a miniscule but important link in the chain, and those unfamiliar with how important the chain is from the panel to the speakers know what I am talking about.

Those who don't get it, or have not chalked up enough experience with decent gear,would say things like " a fuse is not in the signal path".

My friend, everything from the panel to the speaker is in the "signal path".

It's all in how you interpret my bad englishe.
More bad language skills.
I meant to say"those Familiar with how important the chain is from the panel to the speakers"
I should use the preview option I "s'pose."
Aren't you glad that English skills have absolutely no bearing on one's aural acuity or electronics aptitude? =;^)
This has turned into a lively conversation, everybody is thinking. Here is an suggestion regarding sound : If you isolate your power amp ,your pre-amp and your CD player with electromagnetic shielding ( find it on the web , its cheap! ) If you do this ,you will be amazed, nothing short of total sonic improvement will be had...........pure science boys !