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Isoclean Fuse

Recently, I purchased an Isoclean fuse for my ARC VT100 MkII. The value of the fuse for the amp from ARC, is 6.25A / slo-blo type.

When ordering the Isoclean fuse the sales person informed me that Isolclean doesn't have the exact value of 6.25, so I should go up to the next fuse value of 7A (they either had a 6A or 7A).

When I installed the new fuse, what I noticed (and I don't know if this has anything to do with the new fuse) is that the bias of the amp dropped severly (from right at 130mV, down to around 88mV). After installing the new fuse I rebiased the amp but I couldn't get the amp back to 130mV. The best I could get was around 127mV, and this was with the trim pot turned up all the way. (Please note that all biasing was done after letting the amp warm up, with no music playing, for a minimum of 30 minuetes).

Just to check, I removed the Isoclean fuse and inserted the original fuse. Now, the amp showed a bias of 145mV, which I was able to lower back to the proper 130mV setting.

My questions are:

1) Is it OK to substitute a fuse value of 7A for one that is supposed to be 6.25A?
2) Would putting the 7A fuse in the amp cause the amp's bias problem?
3) Are there any other problems that may occur by installing the wrong value fuse?

Any remarks / recommendations that you can make will be appreciated.
louisl
jadem6's avatar
jadem6
1,074 posts
 
Might I suggest using silver contact paste like Walker SST rather than wasting you money on the slower and inferior gold. The fuse is not unique here, only the gold plating...

Also keep in mind how many fuses you may have to protect you circuits. My Sony SCD-1 has three inside and one power, my Plinius SA-102 has four inside and two additional...

Silver treating these will do far more than one $25 fuse in one spot.
louisl OP
183 posts
 
Wow, I didn't intend to start a World War. Come on guys, lighten up a bit.

I'm a tweaker, and firmly believe that certain tweaks can help your system...not become something that it's not, but to improve on what's already there! I can tell you that I've spent much more than $25 for certain tweaks, haven't you? Some worked, others did nothing. Even though $25 for a fuse might seem insane, if it improves the sound, why not? Besides, Artistic Audio is trying to accomodate me by offering to refund my money!

After speaking with ARC, I removed the fuse from the amp (just to be on the safe side) and plan on exchanging it for one that will be a proper fit in my CD player. I'll let everyone know the outcome!

To Jadem6..I did clean the original fuse, and treated it with Caig's "ProGold G5 Contact Enhancer". It was an immediate improvement. I suggest everyone do the same!
aaudio_imports's avatar
aaudio_imports
42 posts
 
For the negative members responding to this posting I suggest you actually try the Isoclean Gold Fuse before you pass judgment on it's performance.

Also for everyone's information the only fuse that needs replacement is the main fuse that supplies power to your component.
wc65mustang
524 posts
 
Artisticaudio
Please stop the tasteless self promotion and advertising.
jadem6's avatar
jadem6
1,074 posts
 
Artistic, I agree I should not pass judgement until I hear them. Perhaps you would loan them out to me as a trial, if I see the improvement, I will buy them, or you will agree to take them back if I find no benifit. If you look at my system posts, you will see I am a self proclaimed tweak freak, and am not usually a na-sayer.

How is it that only the power supply fuse needs changing? My Sony SCD-1 has three interior fuses that appear to be a part of the power supply circuitry. My Plinius SA-102 has two 10 amp fuses per channel as speaker protection. I assume the signal is passed through these, it would seem logical that they are even more prone to sonic quality than the power fuse.

I hope I read this as a non-attacking, non-judgemental post, in that I would like your input. I will let others judge your motives for posting, I was assuming it was to help educate...

jd

PS I was serious about my offer to try them, please email me if you want to take me up on this.
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