This (SW300) has become a fairly rare and sought after driver that gained a considerable amount of praise back in the car sound quality scene of 2005. Its specs really are nothing too spectacular and it doesnt necessarily measure that great response wise in an anechoic chamber, but it has a respectable low resonant frequency (21 HZ), it is efficient (92 DB), it has roughly 1.5 inch excursion capability, and is well made with a very nice aluminum cone, basket, spider, etc.
The suggested volume for automobile use, though probably due to space limitations was around 1.25 sealed, and seeing as how vehicle cabin gain provides a bump in perceived lower output this was an acceptable compromise even though the QTC of the setup would be far from ideal at nearly 1.00 or close to it. At that sealed volume the f3 isnt so great but again for a car it will pass. So I plotted what would be a typically ideal cabinet sealed at the standard .707 QTC and holy crap it calculates for one at 3.5 cubic feet sealed at around 32hz f3. Thats quite a robust enclosure for a sealed application with just one 12 inch driver.
I struck a balance at 2.85 cubic feet and stuffed about a pound of wool in for good measure. I've been feeding it with 500 watts and it can dig really deep on movies like Interstellar and with a bit of boost can really reproduce some nice pipe organ material. Not a bad result for something I had lying around. Cabinet is .75 inch plywood with some decent bracing, front face is 1 inch walnut finished with Danish oil..Thanks for looking!