A subwoofer project, help needed...

[Dxvideo]

Hi all,

I am planning to build a sub for my living room to be used for both music and cinema listening...
Anyway,
After some internet searchings, that guy;
Parts-Express.comayton RSS210HF-4 8" Reference HF Subwoofer 4 Ohm | subwoofer Rss210hf-4 8" subwoofer dayton reference rs sub dayton loudspeaker
looked me great for that project. WinISD says it can produce ~20Hz with 65lt (possible WAF problematics) ported box..
Since that sub driver can handle 200W RMS (400max) then a BPA200 amplifier would be a very good choice for the power amp stage.
Naturally at this point I would need a good subwoofer filter!
I can simply design a 4 poles MFB low pass filter... But this is not what I need exaclty.
Now..
May you advice a subwoofer filter which only controls cut off frequency and phase (just 0 or 180° maybe)..
And may you share your advices about Dayton RSS210HF sub driver pls...

Thanks in advance for your sharings...