What's the difference between DD sub?

Between the 95xx series. Like the h,I, g,etc

Wondering the same. Bump for answer

depends on which one you are comparing. sometimes its cosmetic some times they change small things like top plate thickness, pole venting, baskets, spiders, really if you get say a 9512h and 9512i you more than like like can make the old one the same just by reconing it

Actually the 9500i uses a new basket, suspension, so if you recone to using i softparts, pretty sure you need the new basket as well.