Interestingly I did some new measurements to experiment with some stuff in the bass area today, but I did a full range measurement and noticed that the somewhat strange response at the top end was now completely gone. No dip around 8-9k and also no rise above 10khz. It's now actually pretty flat all the way from 2-20khz.
As far as I know I haven't done much different with the setup/configuration, and I even tried several positions without being able to reproduce the previous humps.. Not sure what happened, but thought it may be worth sharing.
So here the pink line is my current response with the 1723 Tower S (blue was the graph I posted previously for reference).
This is 1/6th smoothing in both measurements.
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