Settings of Descents with Summits
Getting the proper setting is very dependent on positioning of the speakers in your room. Unfortunately, there are no absolute rules for getting this right.
I started out with the phase at 90 degrees (recommended by Martin Logan since the subwoofer is usually at some distance behind or between the speakers). This may not work for all systems.
The easiest way to get the subwoofer to integrate is to experiment with the help of an assistant. Put on low bass source and then have your assistant change the phase step by step until you have the clearest bass (not the most bass). The bass volume setting should be backed off in most cases at the 25 Hz level (I found - 3 to be right for my system). The overall volume should be set so the woofers move with bass (you can feel this if you are next to the speaker).
Most importantly, the subwoofer should not call attention to itself by "pulling" the sound into the corner.