fuses - the $39 ones or the 85 cent ones

Don't mention double blind tests as they are invalid tests for audio.

Tbg, wow, where did that come from? To paraphrase you, certainly you saying DBTs are invalid don't make it so. As Magfan asserts, conducting DBTs would be difficult with hifi but not impossible. Of the actual DBTs I've read about only ten percent or so have shown people hear a difference between the items under test. Those people who statistically show the ability to discern differences are usually practiced listeners. Which you probably are. But again the items under test were items that are accepted, even by most skeptics to have a difference.
IMO many of those people in the audio world who are dead set against DBT have something to lose. For instance, if I sold an item such as a battery operated clock and claimed that by placing the clock in your home your audio system would sound better I wouldn't want that subjected to a DBT.

I wish they would do this test at RMAF.

What would be a low cost $100-200 approach for corner placed bass traps?

Good pont Timrhu. I don't beleive that there are any insurmountable difficulties in setting up a DBT of cables, amplifiers, power cords or whatever; simply a lack of interest by entities that have the resources to fund accurate and probative DBT's (such as pharmaceutical corporations and government agencies). This is in part likely a combination of no financial benefit to the corps and no significant public interest as to the agencies. Furthermore, as to the more ridiculous claims - no one is going to spend the money because there really is no question to be answered .

Magfan, Timrhu, and Pubul57, I will not go through all of the DBT stuff again, but if others do not accept your measure of "sounding better" you can hardly prove anything by using it even were you to use the best experimental procedures. Secondly, no body needs to "prove" anything to you. You are not authorities in the Scam Police. Finally, Magfan in particular seems to react in envy. Just because you cannot yet afford better fuses doesn't mean that you are right that they cannot work or are too expensive for what they do.

Years ago I participated in DBTs at CES, run I think by Stereophile, I had difficulty telling whether our brief listening to an amp was the same amp or a different one. Afterwards, with the amps still hidden I could clearly hear a difference. What would you conclude? One, the brief listening or the same/different task is not the same as what sounds better. Or two, there was no difference in the amps but somehow despite the screen, I was getting clues a to what I preferred. I certainly did not conclude that it didn't matter which amp I bought. If you would embarrass that, fine but don't bother me.

I have consistently found improvement using the IsoClean fuses more so than the Hi-Fi Tuning fuses. Sometimes this is substantial. In my experience I would recommend them to others, but I guarantee nothing. YMMV.

At a recent Stereophile show they had working groups. In one of these, in the first session (early morning), the speaker said that very few folks were able to tell if they were listening to a 30 watt tube amp, or a 200 Watt, 1980s, Denon amp. I'm not sure what that proves, but I found it a bit suprising. In our session, the second session, it did seem that 80% of us were able to tell the which was which almost all the time - it seemed pretty obvious, but that from the bass perfromance, in the midrange it was very, very similar. You would have expected drastic, obvious differences, in the blind test, they were not.