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
Well I own the AMR, HIFI Supremes, Audio Magic, and the Synergistic fuses.
And my choice is...

It depends on the equipment.

The Supremes seem to add larger stage presence but on some equipment they sound bass shy, but on other equipment not so.

SR fuses really sound better with the WA Sticker and have more dynamics with a little more slam in the lower bass and on some equipment its nice and on some its overkill.

Strangely the Audio Magic goes through a mini break in process and at this point (2 days)its hard to tell just how far things can improve. Its a little darker sounding which again sounds good with some equipment and not so with other.

I have the AMR fuses but I have not tried them yet.
No offense boys, but do you really think that if the quality of a fuse was a factor in the sound and performance of a high end amp that the designer of that amp would have addressed it ? Did I hear ....BONEHEADS!!..............
Pack,
Some manufacturers encourage their customers to try higher quality fuses. This is no different than customers who are given the green light to roll different tubes from a builder who used cheaper stock tubes in the component. Most builders can't offer the best available tubes due to cost and target price point considerations. Same is true of capacitors, wire and resistors, it's easy to upgrade these parts to achieve better sound, again manufacturers have cost restraints to factor in terms of final product cost. So a 20 dollar fuse will lose out to a 20 cent fuse with overall final cost comes into play.

Unless a component is cost no object, there will be inevitable compromising to stay within a predetermined price range
You don't seem to get the point, When Nelson Pass designs an amp, every consideration is taken into account in the circuit layout. Ya they cost some bucks,but check out the rail fuses. Pass would laugh at your mumbo jumbo as I do, you tweak guys should pay more attention to physics than some sales "pro". There seems to be no end to the lunacy out there .