These are 3-way Tri-amped speakers based on GR's X-Statik. The bottom with 2x M165 drivers is pretty much the same as the X-Statik. The mid is a single M130 and the tweeter is a deep cup Bohlender Graebener Planar Tweeter. With the help of Norman Tracy who sent me several different baffles to test, this is the final result and I couldn't be happier. They are still breaking in but the sound is already revealing and accurate. These GR speakers are very easy to work with in the crossover design (currently being handled by a mini DSP 4x8). The mid range has a separate tuned and sealed enclosure. The baffle was designed to work with either the open back or closed back Planar tweeter. When I tested it outside with a single open back GRS Planar I got much better results and could take my crossover point much lower but I only have one of them so I stuck with the B&G back cup for now, which might be better anyway because they have to be close to the wall.
Here's the graph with the GRS tweeter and a simple crossover (1st, 2nd and a third order).
The off axis response and waterfall graphs are really clean also.
Thank you Norman Tracy for your work, flawless flat pack and baffle design!
