I'd like to make this clear so that customers don't make mistakes
For sealed subs, turn off rumble filter and set the extension to 14hz/ mid damping before running roomEQ such as Audyssey.
For vented subs with single tuning, set the extension filter to 14hz, low damping before running roomEQ.
For vented subs with dual tuning, plug one port and set the rumble filter to OFF/1, and 14hz low damping before running room EQ.
After the roomEQ is done, you can then play with extension filter and rumble filter setting.
The precaution is to avoid roomEQ accidentally boost frequency below 20hz which can defeat the purpose of having those controls on our amps.This maybe counterintuitive but it is important (because one may think he should use the settings that he wants to use when doing roomEQ). If roomEQ has its way in correcting frequency response, it will undo all the rumble filter, and extension filter setting.