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.
So what's the thinking on using EQ to smooth out narrow peaks and dips in the mid-range? Is the processing sufficient to allow very much? Does it negatively affect sound quality if over done? The reason I ask, is because I was looking at the polars for my sim, and I see a spot or two where I think adding 3dB or more at a Q of around 3 would improve both on, and off axis. Does the optimizer do any of this, if allowed in its setup? Would this just be overkill? I kind of think it would be, but it is interesting.
For example, look at 1.6k and 2k. These two dips are consistent as you move off axis. I assume that if you EQ them on axis, they will also smooth out off axis. These are coming from the mid. I know they are very minor. If the tweeter was crossed below 2k, they would likely be filled by the tweeters response. This is mostly a hypothetical question. I do not usually look at polars, but I think I'm beginning to see why others are fascinated by them.
For example, look at 1.6k and 2k. These two dips are consistent as you move off axis. I assume that if you EQ them on axis, they will also smooth out off axis. These are coming from the mid. I know they are very minor. If the tweeter was crossed below 2k, they would likely be filled by the tweeters response. This is mostly a hypothetical question. I do not usually look at polars, but I think I'm beginning to see why others are fascinated by them.
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