I was looking at your sweeps in REW, and noticed they were over 95dB. That may not be an issue, but you can sweep at a much lower SPL, if in a quiet environment.
I did notice a peak in 2nd order distortion on the mid around 1.5k. It shows both on and off axis. The tweeter measured considerably better at 1.5k. Sometimes a loose mounting screw can cause such a thing. I think an overly tight screw can as well. My driver baskets are thick aluminum. I usually tighten the screws with a minimal amount of torque. The ideal tightness may vary with several factors.
I did notice a peak in 2nd order distortion on the mid around 1.5k. It shows both on and off axis. The tweeter measured considerably better at 1.5k. Sometimes a loose mounting screw can cause such a thing. I think an overly tight screw can as well. My driver baskets are thick aluminum. I usually tighten the screws with a minimal amount of torque. The ideal tightness may vary with several factors.
I was indeed aiming to be near 95dB as I thought this is the common level for checking distortion. Also, I was wary of noise (wind, birds, passing cars and planes), so avoided lower levels, rightly or wrongly. I was getting about 45-51dB headroom readings during REW sweeps.
I was cautious when bolting on the drivers. I am sure they are well attached but not overtightened.
Give it a shot.
It depends on how you setup the optimizer. The way I showed, the output is a blend of on and off axis (in-room), so the optimizer will move the crossover frequencies a little bit, but not much. When I've run it then put the frequencies back it doesn't do much with your design.
If you heavily weight on-axis (or only optimize for it, maybe since you only have an on axis measurement) then it may move the x-over frequencies around and end up screwing up the off axis response.
It depends on how you setup the optimizer. The way I showed, the output is a blend of on and off axis (in-room), so the optimizer will move the crossover frequencies a little bit, but not much. When I've run it then put the frequencies back it doesn't do much with your design.
If you heavily weight on-axis (or only optimize for it, maybe since you only have an on axis measurement) then it may move the x-over frequencies around and end up screwing up the off axis response.