Bedroom sub: 2 x 8" or 1 x 12" sealed vs. 1 x 10" ported; Need driver(s) for 2.1 ft^3

Hi, I'm looking for a subwoofer to put in my bedroom system. It currently conists of a denon dra-395 stereo reciever powering a pair of Phase Tech PC 3.5 6.5" 2 way bookshelfs. I would like a little more bass oomph for music and TV watching (all stereo only).


I'm planning it to be a tall and narrow enclosure with the driver to be front firing and any ports to be on top or bottom. It should be abut 9" deep, 21" wide, and 29" tall. This gives me about 2.1 cubic feet after accounting for board width and driver/port displacement. Would front firing create noise problems? I really cannot do a downfire due to the 9" (unless I went with 8's).


I'm thinking I could either go with two sealed 8's, one ported 10" or one sealed 12". At this point I'm kind of leaning toward a Dayton Titanic Mk III 10" ported and tuned to 25hz with a single 3 x 12" round flared port.


Power would be a 250 wattish plate amp, although might not mount it on the enclosure due to my space restraints.


Any advice on drivers, would a 2x8 setup trump my 1 10", and should I consider a single sealed 12"? Thanks in advance.


PS: Also, do the speaker level outputs on most plate amps apply any kind of highpass signal or are they full range? My reciever does not have any sort of high pass so I'd be looking for a way to do that (maybe build my own passives) after I added the sub.