I'm trying to wrap my head around the 17 tone test, seems very interesting. Have you discussed it already? 100/200/300/400 and roughly third octave spacing above that. It doesn't seem to be about looking at IM sidebands, since groups of tones are harmonically related. I'm assuming that the peaks are a straight line in the input signal, and we're supposed to be looking at the straightness of the peaks in the output signal, but I don't know. Can you provide some insight into this test and how you interpret it?
Cool stuff.