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Re: So what?

I invite Monsterous Mike, Jneutron, and any other 'critics' of Jon Risch and me into this particuliar discussion. How would each of you define harmonic distortion? What do you think the level of 2nd harmonic (for example) is on Arnies graph that SE has provided us? Where would you define your reference level?
For the record, I reiterate once again: I use a 2 stage process. The 1'st stage nulls the fundamental 1KHz tone approximately 95dB and then rescales the distortion output so that -30dBV is always the level of about .01% (-80dB) on my meter. The residual of the meter resides at about .0018% or (-95db). It can be shown with further analysis, that most of this residual, as read by the meter, is the imperfect null which only goes to about 95db or so.
step 2. The spectrum analysis takes over from here and it must to be referenced to the .01%(-80dB) will be at -30dBV. If you look at one of my graphs, you will see the null at -45dB on the graph which is exactly where it should be to be effectively the measurement limit of the meter on the THD analyzer used in step 1.
Since -45db on the second graph is equivalent to -95db (.0018%) on the first stage, we have to add 50 db to subsequent measurements in order to get the measurement levels. In my graphs there is a significant amount of higher order harmonic residual added in some cables, but not others, at about -65db on my graphs. This would be about -115db distortion referenced to the initial 1KHz tone. Some cables have this, some cables don't, Cables are typically tested one after the other, and back to the original. However, the 2 graphs that I submitted to the asylum that Steve refers to, were made at different times and have some dissimilar artifacts, such as the level of the 15.7K TV frequency.

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