What is a recommended sub for this setup?

[dzirkelb]

My home theatre is being pieced together, and I am pretty much ready for the sub. I would like to stay with Polk since the rest are polk, but if one is out there for a better price / sounds better, I will definately buy that.

Center: polk audio cs2
front: polk audio monitor 60
rear: polk audio monitor 30

receiver: Denon AVR-1909
TV: sony Model: KDL-46Z4100/B
Blue Ray: sony 350

Also, I don't recall what sort of cabling is needed for the sub. I think it is a chord that has 2 male ends on each side; hwoever, I dont' recall if there is 2 of them or just one...Can someone help me with that? Or, what that wire is called so I can find a good place to buy one? My current one may do, but I dont't think it is long enough.

I would like the bass to put some good bass out as I do not think I'll be able to place it in the ideal placement of the room due to furniture and doors.