Thank you so much for your comments.
Just to be sure, this is 'L-RTF', the lower plot in the first picture:
View attachment 374918
'R RTF', the lower plot in the second picture, was done the same way:
View attachment 374920
Did I get this right?
These are AVI ADM9.1 speakers. I have no illusions about their directivity profile. It's just the speakers that I have at the moment, for which I wanted to try out the MB method to see if it could work for me.
There are no Klippel measurements available. The best thing I have is the last four graphs in
this post, which indeed show some directivity issues around 3.5kHz, esp. at the port side of the speakers.
I have not created a correction based on this yet, but I'm planning to. Please let me know if there's anything I am still missing.