Look, the first target to add a pair of self powered subwoofers is not to add more bass but to improve the midrange/high frequencies and additional way better bass range.
The target is not: boom, boom but better quality level overall frequency range putting at minimum the I M D and T H D of that two channel room/system.
With out that " putting at minimum IMD/THD " you just can't do it.
That crossing 55ohz of your speakers is just out of target to achieve top high quality overall performance level in any twochannel audio home system.
Yes, that's me but you are the ONE. Good luck.
R.

