I get the best results with ARC with these settings:
- ARC for subwoofer(s) limited to 19 Hz (min EQ frequency) - if I go lower than 18 Hz the results are not good;
- max EQ for subwoofer(s) set to 130 Hz (no need to use limited number of filters for range which will not be used);
- high pass turned off, of course;
- room gain 3 dB;
- crossover for front speakers is set to 60 Hz and for other speakers to 80 Hz.
Manual settings on subs before
- some minor tweaking of PEQs on right subwoofer - it has significant peak at ~22 Hz (it's not just amplitude, but also duration - waterfall diagram shows it very well) and I get better results with ARC if I cut that peak for 5-6 dB before I do ARC calibration.
Manual settings on subs after
- +2 dB volume level on both subs;
- phase set to 30° on both subs which fixes minor dip near the crossover frequency - 30° is value optimal for my system and front speakers, some other will need some other value or maybe 0° is optimal;
- some manual tweaking of PEQs (only negative gain!) on both subwoofers - according to separate measurements for each of them I know which sub is responsible for particular peak in the resulting FR.
Separate measurements of subs (without ARC and PEQs):
Both subs together (without ARC and PEQs):
Full range front speakers without subs (without ARC):
Final result - front speakers with both subs: