By the numbers I get .38 cubic feet per woofer. But Brian has been using them in much larger air spaces. The air space effects the gain that the amp needs to maintain a linear response. It does not effect the response. So there is a lot of flexibility there.
Over on the Rythmik forum, Brian has stated that he has the 8 in drivers and amps ready for sale. I am curious about the enclosure size. To my knowledge, the T/S parms have not been posted (other than VAS).
If I assume T/S parms similar to Danny's 8 in O/B, but with 4 ohm Re (and correspondingly lower Qes), then for a 0.38 cu ft enclosure I get 0.62 Qtc (assuming a non-servo amp), with 200 watts driving near to Xmax for frequencies below 50 Hz. The servo amp would of course make a lower closed loop Q depending on amp settings. So this size enclosure would seem acceptable. But I know that Brian has showed a larger enclosure size (more like 0.7 cuft per driver).
I would like to make several dual 8" drive subwoofers that are small. I'm thinking like 4 to 8 of them that are 12"x12"x15" for a 2 driver box. But I'm a bit worried that I'm missing something (as I'm quite new to this).
One other question - would you use a 1.5" baffle for the front - like is done on the 12"/15" designs, or is 0.75" sufficient?
