fuses - the $39 ones or the 85 cent ones

One additional point, than I'll let this one die a natural death.
The point being that, for most people, the listening area is the last thing modified. Place the speakers, and even spend a couple hours dialing them in. Sub, likewise, but maybe worse, depending on room. Squeeze the furniture in and make room for some wife stuff......depending on how treaty negotiations went!
Now, I know there is a lot of surplus money out there. Our discussion of 39$ (Gasp!) fuses would never come up, if for the price of 3 fuses, you purchased enough OC703 to make a half dozen 2'x4'x4" panels and have a good go at treating your room. I suspect I could improve the imaging of my Maggies thru one of these panels on the wall, in between 'em. Another would go on the 'back' wall which has a bad reflection and since my room is Really odd, vault roof, very asymetrical, I'd experiment with more panels in 'first reflection' points.
I am certain that I could make differences that anyone could hear, maybe spend more than those fuses, and end up with a room / stereo SYSTEM.

Magfan, what makes you think others have not treated their rooms and carefully positioned their speakers? I don't know whether the typical room could be improved as much by what you suggest to rival the improvement of the use better fuses. My experience with room treatments is that those that are effective cost much more than IsoClean fuses. What you are proposing is probably on effective to probably 200 Hz, which is not where most rooms have problems.

Tbg, do you mean down to 200hz or up to 200hz? Controlling bass is the toughest, no? Darn, I guess this should be a new thread, I have some DIY room treatment, but truth is I don't know what I'm doing when it comes to room acoustics (other than I think I have first reflection points covered), but I just can't believe fuses can be anywhere near the order of magnitude (quantitatively and qualitatively) of the changes brought by proper room acoustic treatment which I would think is almost as important(some might argue more so) as the impact of changes in amps/preamps, speakers etc.

Pubul57, yes down to 200Hz.

I do think a bad room is hard to get right and expensive to even attempt it. I think fuses can make a very nice improvement at a reasonable price. Painting the fuse with AVM can also add a lot.

Treating the room should be on the short list.
And, Bass traps aren't that difficult....Corner traps and cylinders are fairly easy.

I just suggest that the right order of operations is room first, than 'icing', if you can even demonstrate differences in fuses!

I don't mean to be harsh, but saying it don't make it so.
Every double blind drug study features a small %age of people getting well on sugar pills or sugar water.

Any room treatment I have done has been obvious and easily heard. Even the spouse, who couldn't care less, makes note of the big changes. She wouldn't say it if she didnt' notice, either. She is pretty honest about these things.

Have fun with hundreds of $'s in fuses, but I think the money could be better spent on the room, 1st.