Here's the response I got from Ty himself:
The new line has totally new drivers that we had developed for us to our specs. It took 6 months for this process and I'm very happy with the Decade line. We used design wiz Danny Ritchie to design the crossovers and he worked with the factory in the driver developement. We had customers at the rocky mt show that liked the D1's better than their Linbrooks and woodmeres so that's the ultimate compliment to me. The D1's are a really big sounding speaker with deep, tight, fast bass and really good resolution. The cabinets are way more high tech than the Linbrooks. They're time aligned so there's very few crossover parts and the mid tweeter baffle is really narrow so the imaging is improved. They also have standard upgrades like flared ports, no rez cabinet damping on the inside of the cabinets, cardas posts mounted in alumium plates and magnetic grills so there's nothing on the front of the speakers degrading the looks.
I have the Linbrook signature 2 piece system and this new D line makes me want to try.