enclosure for DaytonAudio RS75T-8 (WinISD)

The DaytonAudio RS75T-8 3" full-range, 15 watt 8 ohm speaker was recommended to me for this purpose based on the amplifier specs, so I bought some of those (I want to build more than one) and started researching what size enclosure would work best, did a lot of reading, and now I'm thinking two of these drivers, L/R, in a small enclosure similar to lots of the DIY stuff I see out there, like this: 

So I downloaded WinISD an in put all the data I had on the drivers and find that the suggested box is ported, 250 cu inches, with a 93 inch long vent, tuned at ~50Hz.  That seems crazy big for such a small driver.  So I ran ithe driver in WinISD with a sealed enclosure, and the size is down to a more manageable 57 cu inches, but that's tuned at 206Hz, which, I don't know what that means, really, but it seems high.  Plus, sealed isn't recommended.

Any suggestions?

The driver specs are here: http://www.daytonaudio.com/specs/specsheet.php?prod=295-336

And I've uploaded http://169.53.234.202/gs/medias-testgallery/DaytonAudio_RS75T-8.zip - the WinISD wrd driver file here if anyone wants to have a look.

Thanks!

What would you say is your maximum enclosure size? If you want to get anything below 100Hz in less than 3 litres at high volume your options are limited. 

A nifty solution if you want to achieve some actual bass response and are willing to stretch to a 5 litre enclosure would be a pair of P Audio SN3-30N (which I believe at one stage, possibly no longer, was the driver used in the very popular Minirig portable speaker).

Vented to 93Hz with 16.5w of input per driver, these will produce 105dB at 120Hz, but they'll also produce 102.5dB at 83Hz, so you're starting to look at some genuine bass presence with these, especially when used indoors and corner loaded.

The trouble with this driver is getting hold of them. I don't know where to get them. Blue Aran used to sell them, but not anymore: http://speakershop.bluearan.co.uk/index.php?product=P-Audio_SN3-30N_30W_3_inch_Loudspeaker_Driver&id=PAUSN330N ;

(not very useful to you in the US though)

This South African site seems to stock them, but again maybe not much use to you: http://www.pqsound.co.za/index.php?main_page=product_info&products_id=1342

If you're willing to sacrifice volume for bass extension then your options will open up, but I'm not familiar enough with the options to make a decent recommendation. Tangband have some interesting full range drivers so you should have a look at them, and maybe think about some of the larger offerings from Dayton - their 4 and 5" drivers ie.

Your amp will probably drive about 10w per channel into 8ohms with a 12v battery, but that can be increased to 20w if you use a 4ohm driver. So, optimally I would recommend two of the P Audios, 4ohm version. If you can't find those then you have another option which is the P Audio  PA-20K4:

These are actually very similar to the SN3-30N. Perhaps even better in some ways, but I think it's more or less the older/cheaper version of the same driver.

5 litre box, 103.5dB at 83Hz with 16.5w of input per driver. Even if you can't find these in the States I would consider importing.

If a smaller box size is important to you, these would still be preferable for their sheer output potential. In a 2 litre box tuned to 116.7Hz (3.5 x 3cm with 6.5cm or less vent length), a pair of these will output 105.5dB at 120Hz and 108.5dB at 240Hz, and will make full use of the 40w output potential of your amplifier.