All good suggestions. The 12" driver swap is an absolute last resort since the baffle board is mounted from the rear and the speaker (> 80 lb?) is loaded into the entertainment center from the rear. Lots of work moving stuff to do that. Swapping in a JBL 2226 would be easy....oh how I regret not finding the 4pi design before buying those 3015.
So let us get on to some of what I've actually tried...all graphs are 1/6 octave smoothing, mic @ ~42 inches from HF/LF center. These were done over multiple sessions so levels are not the same in each test.
Graph # 1 LE14 eWave
Here's where I'm at with my current set-up using the "LE14" version of the eWave crossover. Designed for different woofer, CD, and waveguide. Looks flat enough on the high end but the acoustic XO is 1840 Hz. I believe the L-pad is set to max or pretty close to it.
Graph # 2 (run 4 - ewave deluxe)
This was what I came up with based on the ewave XO topology used with the 2512 and 3012HO woofers. C1 = 6.2 uF, C2 = 18 uF, L2 = 2.5 mH, R1 = 3 ohms, R2= 7.5 ohms, L1 = 1.0 mH (0.71 ohms). HF is rolling off and I get a peak at 2000 Hz....acoustic XO is 1600 Hz. Trail and error changes in C1, C2, and L2... L-pad at 12:00
Graph # 3 - 4pi
I changed the 4pi to 8 db attenuation (from Wayne's chart). No L-pad.
I don't know if that 6 dB peak is a sign I wired it up wrong or what. Rolls off too early.
Graph # 4 - Z19 XO
I worked up Zilchster's Z19 XO for the Altec Model 19...pretty close anyway, not exact values here or there. Nice camel hump...acoustic XO down to 1400 Hz. Mid/high L-pads at 9:00 and 5:00
So the reason I was looking for a 1.0 to 1.2 kHz XO design for the DE250 was to see if that hump at 2 kHz would go away or if was something I was doing or measuring wrong...and why do all of them roll off too early except for the LE14 version? Is it a problem with HF CD compensation and the high efficiency 3015?
Back to beating on PCD soon enough...