05-12-12: Bryoncunningham
There's a guy over on the Polk Audio forum who claimed his measurements corroborated both that fuses measure differently and that even fuse directions measure differently. You can see his measurements here. I don't really know what to make of it. What do you think?
Hi Bryon,
Thanks for providing the reference, which I have read through.
Looking at the larger spectral components, which are the harmonics of 60 Hz (i.e., 120, 180, 240, 300 Hz etc.) and the DC component, in most of the comparisons between different fuses and different orientations there is essentially no change. In a few cases there are some minor differences, with the expensive fuses being slightly better in some cases and slightly worse in others, compared to the stock fuses.
The most notable differences occur for non-harmonic frequency components that are at levels of 60 or 65 db or so below the amplitude of the 60 Hz component. Those differences were generally in the direction of favoring the expensive fuses, but in some cases favored the stock fuses. But consider that 60 db corresponds to 0.1% in terms of voltage, and 0.0001% in terms of power. And along the lines of Roger's comment, those percentages will be GREATLY reduced by rectification, filtering, and in the case of many components voltage regulation, that occurs in the circuitry between the output side of the fuse and the signal path.
I would add that the differences in those low level spectral components were so small and at such low levels that I wouldn't be surprised if they were attributable to things like differences in the amount of current being drawn through the fuses as a result of differences in the warmup state of the component, or differences in the positioning or orientation of the scope probe or its cable for each of the measurements.
Mapman, thanks very much. Putting aside considerations of the specific individuals being discussed, your comment that
There is such a thing as "technical intuition". This is what enables one to assess technical facts and draw conclusions that have a good chance of being accurate.
strikes me as perceptive and accurate.
Best,
-- Al