Infinity kappa 9 ebay crossover

I've done a few Kappa repairs, I've not been in the 9's.  Either way, I was shocked at how poor quality of coils that were used.  Extremely light gauge coils are used. I doubt that coil impedance was figured into the crossover design, although that is an assumption on my part. I've not measured. This can lend toward impedance and phase angle  issues. So to say Impedance or load can be improved is probable.
The caps, although could be better are not the real weak link in the Kappa Speakers. I have gutted and rebuild 6 & 7's. 

I think to Tim's point, if you get into an Infinity it is not worth it to try and replace parts here and there. They need a modern crossover re-think. Whether you purchase from some one who has done the work for you, or do it yourself, a white paper design is the way to go.

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Bite the bullet and bi-amp those Kappa 9's.  You will love them.

What are the dimensions of your room and ceiling height?