I need some help designing a box for (2) DLS UR12 subs. I have about 36"w x 15"t x 12"d to work with. I am not sure whether to go with sealed or vented but Im leaning towards vented. I am looking for SQL. Here are the details of the subs:

Speaker type : Subwoofer
Impedance : 2 x 4 ohm
Size : 12" (30 cm)
Power handling capacity : 500 W RMS / 800 W max
Frequency range : 20-2000 Hz
Sensitivity : 87,2 dB (1W/1m)
Magnet size : 220 mm (8,7"), 200 oz
Outer diameter : 310 mm (12,22")
Installation depth : 150 mm ( 5,9")
Mounting hole : 282 mm (11,1")
Weight : 13 kg (28,66 lb)
X-max : +- 14 mm (0,55")
Fs: 36,1 Hz Re: 1,85 Qes: 0,32 Qms: 4,98 Qts: 0,3 BL: 16,1 Vas: 24 l (0,85 cuft)
Recommended vented enclosure, voice coils in series or parallel : Volume 27 liter/0,95 cuft, Port: 3" diameter with length 33 cm/13". F3= 37,4 Hz
Recommended sealed enclosure : Volume 16 liters / 0,56 cuft. F3 49,8 Hz

Thanks..