I did tried to change the parts but in the end and after all the frustration, what I have is two NOS JBL 2226J drivers. Positive thing is that those were cheap.
So I will try to make the best out of this.
What is your opinion, is the Dayton audio iMM-6 (mic for phone) + audio tools app (studiosixdigital) good enough to make home brew measurements?
Can you give me advice how to avoid the biggest mistakes when measuring?
Thank you for all the help, I very much like the scientific approach that you have when designing loudspeakers. Math doesn't lie. I personally am tired to build 6.5" two-way speakers. Expensive ones have more refinement but all those lack the easy going, effortless, dynamic sound. Time will tell what the 4pi with the new horn+DE250 and 2226 will bring to the table Coils are already bought and those are 14awg for 2226 and 15 awg for the DE250. Resistors are Mills and Jantzen. 100w 16ohm resistors are from Ebay: