I also want to point out that many, many drivers have break up modes / ringing in the top end of their usable range. Dealing with this is not all that difficult or new.
How it is dealt with in crossover design depends a great deal on the next component up the frequency spectrum. Low pass filters may put the ringig 20-30dB or more down in response making a specific notch filter irrelevant. All the fans of the Focal inverted domes have ultrasonic ringing which they don't seem to complain about very much either. :)
And sometimes we deal with the resonance by designing speakers not to be toed in. :)
Best,
E
How it is dealt with in crossover design depends a great deal on the next component up the frequency spectrum. Low pass filters may put the ringig 20-30dB or more down in response making a specific notch filter irrelevant. All the fans of the Focal inverted domes have ultrasonic ringing which they don't seem to complain about very much either. :)
And sometimes we deal with the resonance by designing speakers not to be toed in. :)
Best,
E