I could be wrong, but I thought Spendor manufactures the LPZ tweeter.They use the same wide-surround soft-dome for all their current models. The only difference is the D-line tweeter is hidden behind the LPZ (linear pressure zone) "microfoil" plate.
The nice thing about buying a Spendor is one gets all their best tech and components in each model. The cost differences result from cabinet size, cabinet construction complexity, and the size and number of drivers. All their current models get magnesium alloy driver baskets, EP77 cones, the wide-surround tweeter, Van Den Hul wiring, high quality crossover parts, and impeccable veneers.