Minimum Box Size for SoundStream SPL160 ?

Hello,  Can anyone help me find the minimum size requirements for a sealed box for a single Sound Stream SPL160 15" sub? I need to build the smallest box possible with out affecting the sound quality. I am assuming that would be a sealed box, but I don't know much about this, so any and all help or suggestions will be greatly appreciated!!!             Thanks !!!

                                                                                        James

http://www.soundstream.com/sub/owner_manual/sp15_160.pdf

You see they have sizes shown for sealed, either 1.5 or 2.0 ft^3  and also show sizes and port sizes for vented enclosures.  All the T/S parameters are listed here.  I ran the parameters through WinISD and it shows an EPB of 80.8...which means it would work best in a vented enclosure.  However, the smallest enclosure for good sound quality would be sealed at 2.0 ft^3

This is a SPL sub, so named for what it does best.  Can you give it 3.4 ft^3 of air space, vented?  If so, put in two (not three) 4" X 16.5" ports.  Your available space would have to include the air space, the driver displacement, the port displacement, the bracing and box walls displacement, too.  This will give you the deepest extension and loudest low bass, tuned at 32 Hz.

There are some varieties of possibilities with this sub if you want to run it through the program.

BTW....it's not always better sound quality with a sealed enclosure.  That's not a cut-and-dried truism.  Your woofer's T/S parameters indicate it would perform to its best in a ported box, so that means you should achieve best SQ from that particular sub in a well-designed and -built vented enclosure.  The EBP is derived from the two parameters Fs (resonant frequency of the driver) and Qes (electrical Q at resonance of the driver).  Fs/Qes=EBP  Yours is 80.8.  EBPs of 50 to 90 can go either way, sealed or ported, but 81 is much closer to 90 than 50. 

If you get the two ports as in my last post suggestion, the combined displacement ot those port tubes would take the box displacement down to 3.0 ft^3 and that's why those particular sizes I showed.  But make sure of the interior volume of the box taking all woofer and bracing into consideration, and also make sure the box is well-braced.  The volume would change with any improvements you make, so the vents would then have to be refigured.  Porting is an exact science to match the port sizes with the box volume....but there is room to work with in whatever volume box you can achieve.  Just think along the lines of bigger is better for that sub.