So I am looking at the ssds on the web and notice the d2 coils have a stronger bl than the d1 coils do and wonder would that difference really make that much of a difference in an enclosure as I know the stronger the bl is the better the sub will react in an enclosure correct me if im wrong. D1 has a bl of 9.3 while the d2 has a bl of 14.1 so somebody help me understand this. Also I need to calculate the subs vas into cu ft it has a vas of 58.7 but I have no clue of how to convert it.

thanks in advance

Just a product of calculating the BL of the voice coils in series.

Honestly it really doesn't matter that much basically match the coil choice to the amplifier that you are choosing to use for the rated power. (amp does power at 1ohm, get the dual 2ohm coils and wire in parallel, if the amp is designed to do power at 2ohms, then do the dual 1ohm coils and wire in series)

So I am looking at the ssds on the web and notice the d2 coils have a stronger bl than the d1 coils do and wonder would that difference really make that much of a difference in an enclosure as I know the stronger the bl is the better the sub will react in an enclosure correct me if im wrong. D1 has a bl of 9.3 while the d2 has a bl of 14.1 so somebody help me understand this. Also I need to calculate the subs vas into cu ft it has a vas of 58.7 but I have no clue of how to convert it.

thanks in advance

This is why you should be comparing the BL^2/Re value. Even then, the difference is not that much.

As for the Vas, there are a little over 28 litres in a cubic foot (28.316 iirc). That should get you started.