synergistic research orange blue fuse direction.

Hi, I have two 611s, one 302 and one 452 McIntosh amps, and I just purchased three Synergistic Research (SR) Orange fuses. I also received one SR Blue fuse free with the purchase of the SR blue receptacle. Would someone advise me with some specificity on the directional installation of the Blue and Orange fuse. Again all the amps are McIntosh.

I am sure another MAC user with SR fuses will chime in. Unfortunately, none of the fuses I know of comes with instructions. IME, one direction will sound more detailed. 
SR has directions that specify the direction of current left right and the fuses are marked left right.  I find it all very confusing.  Thanks for your input.
The difference is not subtle, not at all. In my amp, because of where it goes its impossible to tell which way current goes anyway. So 50/50, stuck it in. Right away noticed big improvement, yet it just did not sound right. Deeper, wider, more dynamic, but somehow messed up. Hard to describe. It got better but within a few minutes I knew it was wrong. Switched direction, night and day.

To think there are people unable to hear such obvious differences, well it just boggles my mind. Especially to then brag to the world: Hey world! I’m deaf! Deaf as a doorknob! And yet, there they go. We should set up a foundation, raise some money, see if we can find a cure.

Meantime listen, flip, listen. You will hear it. Assuming of course you’re not the doorknob.
I am just curious....if you buy a basic fuse direction does not matter.  Why is it that the SR fuses or other high end fuses require proper directionality?
I have tested the basic ceramic fuse that comes stock in the Pass Labs amplifiers that use a fuse.  The fuse does exhibit directionally, but it is not a striking difference. The audiophile fuses I have tried have a greater change in sound depending in the direction they are installed.

The Synergistic Research Blue and Orange fuses should be installed with the "S" closest to the hot side of the fuse holder and the "R" closest to the Neutral side of the fuse holder.  There are at least two ways to decide which side is the hot side. One is to buy an inexpensive circuit tester screwdriver. When touching a hot connection the screwdriver will exhibit a bright light. The less reliable method is to look at the equipment and trace the direction the current flows. This is straight forward when the fuse is located as part of the  inlet for the power cord. Easy to see which side is Hot and which side is neutral. At other fuse locations current direction may not be obvious.The "S" of the Synergistic Research label should be closest to the Hot side.

Of course the other approach is to just listen to music (thirty seconds is plenty) , and keep the fuse in place where the sound is better. This can be done on first installation. You do not need to break in a fuse for 10 days and then test for optimum direction. I have done that rather tedious experiment. No need to repeat that approach.

David Pritchard