Are you assuming the panels are defective because they sound bad (distorted, etc.) or because you don't like the way the plot looks? Assuming it's because of the appearance of the plots:
Your methods and environment are heavily influencing what you measured. Unless you intend to listen at that distance, it's also not going to be representative of a dipole's low-end response in use.
The extreme resolution you have because of your settings is making things look worse than they likely sound. It's typical to have more smoothing in a measurement due to windowing, spatial averaging, or intentional use of smoothing (since narrow deviations in frequency response tend not to affect tonal balance unless they are extreme).
I think you may be expecting closer matching than is typical in planar drivers. This post has a plot of 17 drivers overlaid and discusses this group vs. others that were tested. The scale is different than yours, but there are deviations of similar magnitude to many of those you show, and the plot doesn't have as much resolution as yours, so would likely be equivalent or worse if that aspect was the same.
https://www.diyaudio.com/community/threads/new-planar-drivers-at-parts-express.360339/post-6523979
Your methods and environment are heavily influencing what you measured. Unless you intend to listen at that distance, it's also not going to be representative of a dipole's low-end response in use.
The extreme resolution you have because of your settings is making things look worse than they likely sound. It's typical to have more smoothing in a measurement due to windowing, spatial averaging, or intentional use of smoothing (since narrow deviations in frequency response tend not to affect tonal balance unless they are extreme).
I think you may be expecting closer matching than is typical in planar drivers. This post has a plot of 17 drivers overlaid and discusses this group vs. others that were tested. The scale is different than yours, but there are deviations of similar magnitude to many of those you show, and the plot doesn't have as much resolution as yours, so would likely be equivalent or worse if that aspect was the same.
https://www.diyaudio.com/community/threads/new-planar-drivers-at-parts-express.360339/post-6523979