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,
milpai

Showing 3 responses by toolbox149

Indranil

"auxinput- I ended up ordering Hifi Tuning Silverstar (the main fuse) and Classic Gold (rail fuses) which are on their way. I would first try the main fuse to see if this improves the sound at all. If yes then I would replace the rail fuses. I would post all result hopefully by the end of next week.
I wanted to find if folks here have an idea of how much changing the rail fuse would contribute to the overall improvement in sound under the assumption that changing fuse improves sound quality. Any feedback would be greatly appreciated.
Also did anybody compare performance across Hifi Tuning (Classic Gold, Silverstar, Supreme) and Synergistic Research Quantum Black fuses?

Thanks.
Indranil"

I am a big believer in the HiFi Tuning silver fuses. I have about a dozen components in my system and have a similar situation as you do with my Adcom amps. I too have purchased silver fuses for my main amp fuses and, I also first bought and tried 4 gold fuses for my Rails.
My first degree was in music. While my principal instrament was the string bass and electric bass, the main focus of my study was leaning toward music arranging. I love hearing all the detsils in music. The breathiness and occational sharpness of reeds, the initial draw of a bow, not to mention all the vaious percussion instraments.
Now your mileage may vary, but clearly hearing these details is why I like the silvers so much. The silvers bring out the details that I love without sacrificing too much warmth. Seems like regardless of whether it's tubes or fuses, it's always a balancing act between sharpness/detail and/or warmth/analog. I've tried a number of different fuses, AMR, HiFi Tuning, SR, etc. I keep coming back to the silvers.
There is a BIG difference between the silvers and the golds. While the silvers are very detailed with some warmth, the golds are very warm, but you sacrifice some of the detail.
My own experience with fuses is once you have about 30 hours on them, you're going to have a pretty darn good idea of what they will sound like when they are fully burned in. They won't be doing an about-face on you.
So put the silver main fuse in your amp (on my Adcoms this made a very noticeable improvement), put some hours on the fuse and get used to what it sounds like. After that, have fun inserting the golds, doing one at a time to gauge directionality of each rail fuse.
Just a side note: Most of my components were impressively improved by upgrading fuses but a couple, like my two tube preamps, gained no benefit whatsoever - likewise in many of my components the fuse was directional, but in some areas music sounded the same in either direction. In the case of my rail fuses I didn't hear a difference based on fuse directionality.
Now, here's a little advice from tube rolling experience. Hopefully, you will like the way your amp sounds after the five new fuses but if you don't, there are some ways to ultimately get to where your ears Will be liking what they hear.  If you think the silver fuse is too bright after 30-40 hours, note how it sounds and then put the gold fuses in. The gold fuses will temper the detail/brightness of the silver and you might have good balance of detail and warmth. For me, the silver was fantastic sounding but when I added the four gold fuses into my rails, my amps sounded overly warm and I lost some of my precious detail.
Jim McShane, of audio tube fame, once told me you need to match tube types when they are a left channel/right channel pairing. So, the tubes in V1-V2 need to match, and the tubes in V3-V4 need to match, and V5-V6 need to match; but the tubes in V1-V2 do not need to match the tubes in V3-V4, etc.
So, when I put the 4 gold fuses in my Adcoms & the sound turned way too warm & analogy for my taste, I pulled one gold out of the left side and the right side rails and re-inserted one original fuse in each side giving me an original and a gold for each side. As if by magic, I now had a sound that was just a little bit warmer than before the golds were first tried and I still had my detail and slam.
I just recently bought silvers to try in the rails. I'm now using one silver and one gold in the left and right rail channels in two of my Adcoms.  unfortunately, I only have about 10 hours on them so I can't make a final decision. If you want I'll keep you posted.
Indranil

Your experience is an exact replication of my results. The silver in the main was excellent but when I added the four golds in the rails, the overall sound was way too warm with a loss of upper mid-range detail for my tastes.  It was warm to the point of getting a little muddy.

I would recommend burning them in for at least 30 hours before you start making any decisions. Like I said above, whether your burning in tubes or fuses, after about 30 hours of burn in, you'll have a pretty darn good idea what they will ultimately sound like. 

If after 30 hours of burn in, you still don't like the sound, try replacing two of the gold fuses with your original fuses. So, each rail side L & R will have a gold fuse and an original fuse.  That sounded better to me.   Now I have a silver and a gold on each side of my rails, which is a very nice balance.  I see where you can't get silvers anymore, so hopefully the gold & original combo will work well for you.

If you somehow can get a couple of silvers, if possible I would only buy two and do a silver and a gold combo in each side of your rails.  Four silvers in the rails plus a silver in the main fuse might become too bright rendering details like female vocals and brass instruments a little harsh.  Too much of a good thing.

Do you have any tube equipment in your set-up?

Just remember it's not whether you have all of your fuses upgraded or half of your fuses upgraded.  If you like the resulting sound, you're the big winner!  So then just sit back and enjoy the music.

Toolbox

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.