Synergistic Red Fuse ...

^^^

Something isn't right. There should be a huge improvement over a stock fuse. Direction is a trial and error thing just like the RED and BLACK fuses. 

Frank

Jafreeman 9-27-2017
I am hoping Almarg and peers will answer my question about AC mains and the functions of their fuses, as I am quite surprised with the sonic gift they are providing.

I can’t explain that, Joe. Obviously a 10 amp fuse comes a bit closer to being no fuse than a 7 or 8 amp fuse that is otherwise similar, at least in terms of lower resistance, lower voltage drop, and reduced fluctuations in voltage drop as current demand fluctuates. But I would expect both those differences and any resulting sonic differences to be small, especially between the 8 and 10 amp Black fuses you’ve tried. And especially with a robustly designed amp such as the REF 210, which per its description at arcdb.ws has numerous internal voltage regulators, large amounts of energy storage in its power supply (787 joules), and does not have a huge difference between its current draw at idle and at max power (that difference being well under 2:1).

Unrelated to the fuse question, though, after looking at your system description it appears that you are connecting your REL subs at speaker-level, and I assume you are using the balanced inputs of each sub, since the amps are fully balanced. Assuming that is the case, I’m wondering where you are connecting the ground wire from the subs (i.e., what would be the black wire in a typical REL Speakon cable)?

Regards,
-- Al

there is no  direction information on fuse and it looks same on both sides.  I only changed fuse on PreAmp for now to test so that i can buy more in future but don't hear any difference what so ever.  

Here is my system info. 

Vandersteen 7 II
ARC REF 5SE
ARC REF 250SE
ARC REF 2SE 

veerapaneni
I got blue fuse for my ARC REF 5SE but don’t hear any difference in sound when compared to OEM fuse.

That’s because you are immune to "expectation bias." Send it back for a refund.

veerapaneni
There is no direction information on fuse and it looks same on both sides, but don't hear any difference what so ever.  

Because it’s an ac fuse and it doesn’t matter, even if it were a dc fuse it still wouldn’t matter.

Cheers George

@veerapaneni 

I own ARC LS28, try inserting the fuse with 'SR' lettering pointing towards the chassis. 

As others have suggested, try both directions and let your ears determine the 'right' installation.