Hi-Fi Tunig Fuses & Parasound A21


Hi,
Have any Parasound A21 owners replaced the stock fuses with the Hi-Fi Tuning fuses in their amp? I understand that there are four 8A slow blow internal fuses and one 12A slow blow fuse on the rear panel. This is a awesome amp as-is. Just my curiosity.

Please share your experiences.

-Thanks,
128x128milpai
I don’t have an electrical engineering degree that might help inform me as to why things in this quizzical hobby happen as they do but they do occur. There is plenty of anecdotal evidence of such all over this site. Perhaps the mystery is part of the appeal.
Its the voltage drop across the fuse. You can hear it and measure it when the fuse is correct in its holder. Its easy to measure. If the fuse is on a circuit board, I find it more expedient to spin the fuse in its contacts until you see a lower voltage drop rather than reversing it.

The variable voltage drop caused by the fuses and fuse holders not being perfectly dimensioned is what has given rise to the idea that they are directional. They aren't (and can't be, if they were they could not be used in AC circuits); its just that sometimes when you reverse them you're getting a better connection. Its really that simple- no mystery and easy prove through measurement. If you want it to remain mysterious though, just don't measure the voltage drop across the fuse :)
I think it's dangerous to introduce actual scientific facts into the Fuse Voo Doo world as it is VERY important to retain the mystery of fuses as entire business models rely on this. Atmasphere continues to toss these facts into the mix willy nilly regardless of being utterly ignored by the fuse magic faithful. Those who insist that their uber sensitive ears verify directionality as well as other Incredible Things provided by Inherint Fuse Magic (IFM) are nothing less than fragile souls seeking to make life better through imagination…no explanation is needed regarding how or why these fuses were developed to do whatever they do as long as they A: cost much more than those lame "non magic" fuses, and B: have somebody else reporting on the astonishingly positive sonic results ("Cellos sound better") of IFM while remaining oblivious of the lack of any rational explanation of how it does that. 
"She has an illusion, and you have reality. May you find your way as pleasant."

- The Keeper 
@Toolbox,
All my components are solid state. No tube so far... it's about 36 hrs that these gold fuses are added to the amplifier and the haziness specially with instruments and drums continues. The overall sound is still constricted which is expected during the break-in time but the haziness i am not sure. I will continue running the amp another 36 hrs and then start changing the fuse configuration. will definitely try the layout as you suggested... If this haziness continues with the gold fuses with all or any combination then they have to go. Unfortunately Silver star fuse in 8 Amp is not available anywhere except Music Direct which has only two offered at the full price. I have ordered a set of 4 Synergistic Research SR fuses which will be delivered early next week. So after 76 hrs or so if the current combination of all gold fuses doesn't improve the sound most importantly cures the smearing of the sound I will try other alternatives including what you suggested and also the SR fuses in the amplifier. I will keep you (whoever is interested) posted.
Thanks.
Jetter
sorry geoff,

wolf_garcia +1

we now have a trifecta

Holy guacamole! A double bingo. What are the odds! Are you guys from the same holler?

😛


Indranilsen, 

Your experience is sounding more and more like mine.  If you gave the HFT Golds a good listen at 20 hours and again at 36 hours, I'm pretty confident when you listen to them at 76 hours, you'll find the Golds to be more refined, smoother, a little closer to neutral sounding.  Inforunately, the loss of detail (haziness) will probably continue to be a problem for you. Especially since your post sounds like the haziness of the Golds is a substantial distance away from what you ultimately want to hear.  Not even close.  
If you had stated that the Golds only lost a little bit of the detail you desire, I'd say keep burning them in til they have 150-200 hours on them. But, just like a leopard doesn't change its spots, a tube or a fuse that is warm but less detailed won't suddenly start producing a a clear, detailed sound.  Whether it's tubes or fuses seems like you always have to decide: warm but smears the details vs. detailed but lacking warmth.
I'm going to be interested in your experience with the SR fuses.  A short while ago I decided to try a SR Red fuse in my preamp.  I found the Red to produce somewhat similar results as the HFT Gold fuses. The Red fuse was not quite as warm as the Golds, but the Red didn't loose as much of the details either.
I was all set to send the Red back, but that's when I received the last of my HFT Silvers to add to the two Gold rail fuses already in my amp.  I think adding the two Silvers to the two Golds in my rails would have resulted in a sound that was too bright and a little sterile. Keeping the overly warm Red in my preamp balanced off the two new Silvers, bringing me back to where I ultimately wanted to be.
I'll be interested to find out how the SR fuses compare to the Golds, although I have to admit, I think my days of fuse rolling are over.  Seems like I've found the sound I like and any change that a new fuse makes in my sound requires that I change something else to return the sound to where it was.  
Ah yes, there is an end to all this madness.

I recently replaced all the fuses in my a 21 with hi-fi tuning supreme fuses. As others have noted, you hear an immediate improvement in speed and resolution when you replace the back panel fuse. When you replace the fuses in the rails, an additional improvement in these characteristics result, along with an improvement in the weight of the sound.

I experimented with Furutech TF audio file fuses. With a hi-fi tuning fuse in the back panel, and four. Tech fuses in the rails, the sound was too forward, warm, and slow for my ears. The best set up was a hi-fi tuning fuse in the back panel, a pair of. Tech fuses in the outside rails, and stock fuses in the inside rails. This gave a uncanny, lifelike presence to vocals. But the resolution of sounds from instruments was less sharp than with the all hi-fi tuning fuse set up. If you really like listening to vocal music and to rock, this might be your set up. Electric guitars are reproduced with a lot of energy and a bright tone.
I also experimented with mixing stock fuses with hi-fi tuning supreme fuses in the rails: two stock fuses in the inside rails and hi-fi tuning supreme fuses in the outside rails. The all hi-fi tuning supreme set up was better by a small margin, greater speed and resolution and more lifelike.
My system: Bluesound Vault 2 --> Parasound Halo JC2BP --> A21 --> Vandersteen Quatro Wood CT.
So, I have a question. How did you establish the correct direction for so many fuses and combinations? Just curious.

@geoffkait 
The HiFi Tuning Fuses are marked with an arrow. When I placed the fuses, I put the arrow in the same direction as the flow of current.The stock and Furtuech fuses are unmarked. I did not test opposite directions.
I also did not test all possible combinations of fuses, so there are other ways in which my test was incomplete.
I place some confidence in my observations because they consistent with characterizations others have made of HiFi Tuning and Furutech fuses.
Cheers.
The HiFi Fuses are marked with diode symbols and, as I understand it, the direction of the diode “arrow” is random. So, you need to try both directions. The diode symbol is useful in knowing which way the fuse was oriented just before you changed directions.

For multiple fuses the only rational way to test for direction is start with one fuse, change direction and listen. Decide which direction sounds better, then move to the next fuse. After completely this test for all fuses repeat, in case you were uncertain about a fuse’s direction the first time around. As you proceed the sound will improve and make it easier to hear fuse directionality.

@geoffkait
Hey.
Flipped a fuse.
Ka-boom!
I flipped the fuse on the left inside rail. Perfection. Sound snapped into place. Before the edge of vocals were just a bit blurry. Very subtle difference. But difference between perfection and not.
Slim evidence on which to conclude changing the direction of the fuse was the cause.  A more convincing demo would have required flipping it back and back again to check if change in sound was specific to change in direction of fuse. And, experimenting with flipping other fuses. It is possible I had other fuses right and just this one wrong. Maybe I got lucky.
Regardless, I owe you thanks.
Very happy with sound. Not touching a thing.

Appreciate your knowledge. Enjoy your mischievious posts.