I did a comparison between the various plug-in filters. Not surprisingly, the XPPF with its low-pass topology performed the best. The XTB-F10, F15, and F15+ all performed better than the 15 amp AF120. All are notch filters centered at 120KHz. Loading of the XTB-F15+ is almost as good as the XTB-F10.
Filter comparison:
Maxi Controller unloaded 7.44V
Maxi Controller with XPPF load 7.28V
Maxi Controller with XTB-F10 6.80V
Maxi Controller with XTB-F15 5.92V
Maxi Controller with XTB-F15+ 6.60V
Maxi Controller with AF120 5.92V
Noise generator direct to line .82V
Noise generator through XPPF .00V
Noise generator through XTB-F10 .00V
Noise generator through XTB-F15 .00V
Noise generator through XTB-F15+ .00V
Noise generator through AF120 .01V
Maxi Controller direct to line 7.44V
Maxi Controller through XPPF .00V
Maxi Controller through XTB-F10 .00V
Maxi Controller through XTB-F15 .00V
Maxi Controller through XTB-F15+ .00V
Maxi Controller through AF120 .03V
Measurements were made with the XTBM-Pro and each filter plugged into the powerstrip on my workbench.
Jeff