Did DST get back to you about the B12? What did they say?

Maybe your request about having them build the B12 got them the idea to make a higher Qts version of their original XLS 830500 12". I mentioned to you ages ago I used to use the XLS 12" as my home sub in a dual passive radiator alignment, was a great low distortion sub but needed EQ to get the low end up because it had very low Qts of 0.20.

XXLS looks exactly the same as XLS except with higher Qts and slight change in other parameters to suit, similar specs to the LAB12 really. Perhaps it was so more people could use it without EQ, but main factor probably was so required box volume is larger (XXLS 12" best in 80-90L ported box) as basically the older XLS series had to have passive radiators as required box volume was between 35L and 50L for the 12" and meant no sane port size would fit in!

Adrian