Ralph,
At what frequencies does the harmonic issues occur?
I am not aware of any speaker system that is said to be able to pass a sin wave unaltered so perhaps nothing unusual in sin wave artifacts, chose your type or not.
Original OHM A or F full range Walshes perhaps, but I think even those only went to 16 khz or so.
Maybe when I was 18 years old and tested as able to hear pretty much up to 20khz I would have heard something.
I think for every digital artifact one could point out a different one with analog to counter, so chose your artifacts.
Some matter more than others . To me, if I don't hear it, it doesn't matter. If others do, I suppose it does.